diff --git a/messages/de.msg b/messages/de.msg
index de6d18014..8b271d82e 100644
--- a/messages/de.msg
+++ b/messages/de.msg
@@ -12,7 +12,7 @@ DeRegUntil: Abmeldungen bis
 SummerTerm year@Integer: Sommersemester #{display year}
 WinterTerm year@Integer: Wintersemester #{display year}/#{display $ succ year}
 SummerTermShort year@Integer: SoSe #{display year}
-WinterTermShort year@Integer: WiSe #{display year}/#{display $ succ year}
+WinterTermShort year@Integer: WiSe #{display year}/#{display $ mod (succ year) 100}
 PSLimitNonPositive: “pagesize” muss größer als null sein
 Page n@Int64: #{display n}
 
@@ -34,29 +34,29 @@ CourseRegisterOk: Sie wurden angemeldet
 CourseDeregisterOk: Sie wurden abgemeldet
 CourseSecretWrong: Falsches Kennwort
 CourseSecret: Zugangspasswort
-CourseNewOk        tid@TermId courseShortHand@Text: Kurs #{display tid}-#{courseShortHand} wurde erfolgreich erstellt.
-CourseEditOk       tid@TermId courseShortHand@Text: Kurs #{display tid}-#{courseShortHand} wurde erfolgreich geändert.
-CourseNewDupShort  tid@TermId courseShortHand@Text: Kurs #{display tid}-#{courseShortHand} konnte nicht erstellt werden: Es gibt bereits einen anderen Kurs mit dem Kürzel #{courseShortHand} in diesem Semester.
-CourseEditDupShort tid@TermId courseShortHand@Text: Kurs #{display tid}-#{courseShortHand} konnte nicht geändert werden: Es gibt bereits einen anderen Kurs mit dem Kürzel #{courseShortHand} in diesem Semester.
+CourseNewOk        tid@TermId courseShortHand@CourseShorthand: Kurs #{display tid}-#{courseShortHand} wurde erfolgreich erstellt.
+CourseEditOk       tid@TermId courseShortHand@CourseShorthand: Kurs #{display tid}-#{courseShortHand} wurde erfolgreich geändert.
+CourseNewDupShort  tid@TermId courseShortHand@CourseShorthand: Kurs #{display tid}-#{courseShortHand} konnte nicht erstellt werden: Es gibt bereits einen anderen Kurs mit dem Kürzel #{courseShortHand} in diesem Semester.
+CourseEditDupShort tid@TermId courseShortHand@CourseShorthand: Kurs #{display tid}-#{courseShortHand} konnte nicht geändert werden: Es gibt bereits einen anderen Kurs mit dem Kürzel #{courseShortHand} in diesem Semester.
 FFSheetName: Name
 TermCourseListHeading tid@TermId: Kursübersicht #{display tid}
 TermCourseListTitle   tid@TermId: Kurse #{display tid}
 CourseNewHeading: Neuen Kurs anlegen
-CourseEditHeading tid@TermId courseShortHand@Text: Kurs #{display tid}-#{courseShortHand} editieren
+CourseEditHeading tid@TermId courseShortHand@CourseShorthand: Kurs #{display tid}-#{courseShortHand} editieren
 CourseEditTitle: Kurs editieren/anlegen
 
 Sheet: Blatt
-SheetList          tid@TermId courseShortHand@Text: #{display tid}-#{courseShortHand} Übersicht Übungsblätter
-SheetNewHeading    tid@TermId courseShortHand@Text: #{display tid}-#{courseShortHand} Neues Übungsblatt anlegen
-SheetNewOk         tid@TermId courseShortHand@Text sheetName@Text: Neues Übungsblatt #{sheetName} wurde im Kurs #{display tid}-#{courseShortHand} erfolgreich erstellt.
-SheetTitle         tid@TermId courseShortHand@Text sheetName@Text: #{display tid}-#{courseShortHand} #{sheetName}
-SheetTitleNew      tid@TermId courseShortHand@Text               : #{display tid}-#{courseShortHand}: Neues Übungsblatt
-SheetEditHead      tid@TermId courseShortHand@Text sheetName@Text: #{display tid}-#{courseShortHand} #{sheetName} editieren
-SheetEditOk        tid@TermId courseShortHand@Text sheetName@Text: Übungsblatt #{sheetName} aus Kurs #{display tid}-#{courseShortHand} wurde gespeichert.
-SheetNameDup       tid@TermId courseShortHand@Text sheetName@Text: Es gibt bereits ein Übungsblatt #{sheetName} in diesem Kurs #{display tid}-#{courseShortHand}.
-SheetDelHead       tid@TermId courseShortHand@Text sheetName@Text: Übungsblatt #{sheetName} wirklich aus Kurs #{display tid}-#{courseShortHand} herauslöschen?
+SheetList          tid@TermId courseShortHand@CourseShorthand: #{display tid}-#{courseShortHand} Übersicht Übungsblätter
+SheetNewHeading    tid@TermId courseShortHand@CourseShorthand: #{display tid}-#{courseShortHand} Neues Übungsblatt anlegen
+SheetNewOk         tid@TermId courseShortHand@CourseShorthand sheetName@SheetName: Neues Übungsblatt #{sheetName} wurde im Kurs #{display tid}-#{courseShortHand} erfolgreich erstellt.
+SheetTitle         tid@TermId courseShortHand@CourseShorthand sheetName@SheetName: #{display tid}-#{courseShortHand} #{sheetName}
+SheetTitleNew      tid@TermId courseShortHand@CourseShorthand               : #{display tid}-#{courseShortHand}: Neues Übungsblatt
+SheetEditHead      tid@TermId courseShortHand@CourseShorthand sheetName@SheetName: #{display tid}-#{courseShortHand} #{sheetName} editieren
+SheetEditOk        tid@TermId courseShortHand@CourseShorthand sheetName@SheetName: Übungsblatt #{sheetName} aus Kurs #{display tid}-#{courseShortHand} wurde gespeichert.
+SheetNameDup       tid@TermId courseShortHand@CourseShorthand sheetName@SheetName: Es gibt bereits ein Übungsblatt #{sheetName} in diesem Kurs #{display tid}-#{courseShortHand}.
+SheetDelHead       tid@TermId courseShortHand@CourseShorthand sheetName@SheetName: Übungsblatt #{sheetName} wirklich aus Kurs #{display tid}-#{courseShortHand} herauslöschen?
 SheetDelText       submissionNo@Int: Dies kann nicht mehr rückgängig gemacht werden! Alle Einreichungen gehen ebenfalls verloren! Es gibt #{display submissionNo} Abgaben.
-SheetDelOk         tid@TermId courseShortHand@Text sheetName@Text: #{display tid}-#{courseShortHand}: Übungsblatt #{sheetName} gelöscht.
+SheetDelOk         tid@TermId courseShortHand@CourseShorthand sheetName@SheetName: #{display tid}-#{courseShortHand}: Übungsblatt #{sheetName} gelöscht.
 
 SheetExercise: Aufgabenstellung
 SheetHint: Hinweis
@@ -80,21 +80,21 @@ Deadline: Abgabe
 Done: Eingereicht
 
 Submission: Abgabenummer
-SubmissionsCourse tid@TermId courseShortHand@Text: Alle Abgaben Kurs #{display tid}-#{courseShortHand}
-SubmissionsSheet sheetName@Text: Abgaben für Blatt #{sheetName}
+SubmissionsCourse tid@TermId courseShortHand@CourseShorthand: Alle Abgaben Kurs #{display tid}-#{courseShortHand}
+SubmissionsSheet sheetName@SheetName: Abgaben für Blatt #{sheetName}
 SubmissionWrongSheet: Abgabenummer gehört nicht zum angegebenen Übungsblatt.
 SubmissionAlreadyExists: Sie haben bereits eine Abgabe zu diesem Übungsblatt.
-SubmissionEditHead tid@TermId courseShortHand@Text sheetName@Text: #{display tid}-#{courseShortHand} #{sheetName}: Abgabe editieren/anlegen
-CorrectionHead tid@TermId courseShortHand@Text sheetName@Text cid@CryptoFileNameSubmission: #{display tid}-#{courseShortHand} #{sheetName}: Korrektur
+SubmissionEditHead tid@TermId courseShortHand@CourseShorthand sheetName@SheetName: #{display tid}-#{courseShortHand} #{sheetName}: Abgabe editieren/anlegen
+CorrectionHead tid@TermId courseShortHand@CourseShorthand sheetName@SheetName cid@CryptoFileNameSubmission: #{display tid}-#{courseShortHand} #{sheetName}: Korrektur
 SubmissionMember g@Int: Mitabgebende(r) ##{display g}
 SubmissionArchive: Zip-Archiv der Abgabedatei(en)
 SubmissionFile: Datei zur Abgabe
 SubmissionFiles: Abgegebene Dateien
-SubmissionAlreadyExistsFor user@Text: #{user} hat bereits eine Abgabe zu diesem bÜbungsblatt.
+SubmissionAlreadyExistsFor email@UserEmail: #{email} hat bereits eine Abgabe zu diesem bÜbungsblatt.
 
 CorrectionsTitle: Zugewiesene Korrekturen
 CourseCorrectionsTitle: Korrekturen für diesen Kurs
-CorrectorsHead sheetName@Text: Korrektoren für Blatt #{sheetName}
+CorrectorsHead sheetName@SheetName: Korrektoren für Blatt #{sheetName}
 
 Unauthorized: Sie haben hierfür keine explizite Berechtigung.
 UnauthorizedAnd l@Text r@Text: (#{l} UND #{r})
@@ -109,21 +109,23 @@ UnauthorizedParticipant: Sie sind nicht als Teilnehmer für diese Veranstaltung
 UnauthorizedCourseTime: Dieses Kurs erlaubt momentan keine Anmeldungen.
 UnauthorizedSheetTime: Dieses Übungsblatt ist momentan nicht freigegeben.
 UnauthorizedSubmissionOwner: Sie sind an dieser Abgabe nicht beteiligt.
+UnauthorizedSubmissionRated: Diese Abgabe ist noch nicht korrigiert.
 UnauthorizedSubmissionCorrector: Sie sind nicht der Korrektor für diese Abgabe.
 OnlyUploadOneFile: Bitte nur eine Datei hochladen.
 DeprecatedRoute: Diese Ansicht ist obsolet und könnte in Zukunft entfallen.
 UnfreeMaterials: Die Materialien für diese Veranstaltung sind nicht allgemein freigegeben.
 MaterialFree: Kursmaterialien ohne Anmeldung zugänglich
 UnauthorizedWrite: Sie haben hierfür keine Schreibberechtigung
+UnsupportedAuthPredicate tag@String shownRoute@String: "!#{tag}" wurde auf eine Route angewandt, die dies nicht unterstützt: #{shownRoute}
 
 EMail: E-Mail
-EMailUnknown email@Text: E-Mail #{email} gehört zu keinem bekannten Benutzer.
-NotAParticipant user@Text tid@TermId csh@Text: #{user} ist nicht im Kurs #{display tid}-#{csh} angemeldet.
+EMailUnknown email@UserEmail: E-Mail #{email} gehört zu keinem bekannten Benutzer.
+NotAParticipant email@UserEmail tid@TermId csh@CourseShorthand: #{email} ist nicht im Kurs #{display tid}-#{csh} angemeldet.
 TooManyParticipants: Es wurden zu viele Mitabgebende angegeben
 
 AddCorrector: Zusätzlicher Korrektor
-CorrectorExists user@Text: #{user} ist bereits als Korrektor eingetragen
-SheetCorrectorsTitle tid@TermId courseShortHand@Text sheetName@Text: Korrektoren für #{display tid}-#{courseShortHand} #{sheetName}
+CorrectorExists email@UserEmail: #{email} ist bereits als Korrektor eingetragen
+SheetCorrectorsTitle tid@TermId courseShortHand@CourseShorthand sheetName@SheetName: Korrektoren für #{display tid}-#{courseShortHand} #{sheetName}
 CountTutProp: Tutorien zählen gegen Proportion
 Corrector: Korrektor
 Correctors: Korrektoren
@@ -187,6 +189,7 @@ Passed: Bestanden
 NotPassed: Nicht bestanden
 RatingTime: Korrigiert
 RatingComment: Kommentar
+SubmissionUsers: Studenten
 
 RatingPoints: Punkte
 RatingFiles: Korrigierte Dateien
diff --git a/models b/models
index 0fbb50c92..e68c47c43 100644
--- a/models
+++ b/models
@@ -2,7 +2,7 @@ User json
     plugin         Text
     ident          Text
     matrikelnummer Text Maybe
-    email          Text
+    email          (CI Text)
     displayName    Text
     maxFavourites  Int default=12
     theme          Theme default='Default'
@@ -48,9 +48,10 @@ Term json
     Primary name       -- newtype Key Term = TermKey { unTermKey :: TermIdentifier }
     deriving Show      -- type TermId = Key Term
 School json
-    name          Text 
-    shorthand     Text
+    name          (CI Text)
+    shorthand     (CI Text)
     UniqueSchool name
+    UniqueSchoolShorthand shorthand
     deriving Eq    
 DegreeCourse json
     course       CourseId
@@ -58,10 +59,10 @@ DegreeCourse json
     terms        StudyTermsId
     UniqueDegreeCourse course degree terms
 Course 
-    name             Text
+    name             (CI Text)
     description      Html Maybe
     linkExternal     Text Maybe
-    shorthand        Text
+    shorthand        (CI Text)
     term             TermId
     school           SchoolId
     capacity         Int64 Maybe
@@ -72,6 +73,7 @@ Course
     registerSecret   Text Maybe        -- Falls ein Passwort erforderlich ist
     materialFree     Bool
     CourseTermShort  term shorthand
+    CourseTermName   term name
 CourseEdit
     user         UserId
     time         UTCTime
@@ -81,6 +83,7 @@ CourseFavourite
     time         UTCTime
     course       CourseId
     UniqueCourseFavourite user course
+    deriving Show
 Lecturer 
     user         UserId
     course       CourseId
@@ -92,7 +95,7 @@ CourseParticipant
     UniqueParticipant user course
 Sheet
     course          CourseId
-    name            Text
+    name            (CI Text)
     description     Html Maybe
     type            SheetType
     grouping        SheetGroup
diff --git a/routes b/routes
index 27263ba9a..f207525b7 100644
--- a/routes
+++ b/routes
@@ -50,14 +50,14 @@
 -- For Pattern Synonyms see Foundation
 /course/                    CourseListR       GET             !free
 !/course/new                CourseNewR        GET POST        !lecturer
-/course/#TermId/#Text       CourseR                           !lecturer:
+/course/#TermId/#CourseShorthand CourseR                           !lecturer:
   /                           CShowR          GET             !free
   /register                   CRegisterR          POST        !timeANDcapacity
   /edit                       CEditR          GET POST
   /subs                       CCorrectionsR   GET POST
   /ex                         SheetListR      GET             !registered !materials
   !/ex/new                    SheetNewR       GET POST
-  /ex/#Text SheetR:
+  /ex/#SheetName SheetR:
     /                           SShowR        GET             !timeANDregistered !timeANDmaterials !corrector
     /edit                       SEditR        GET POST
     /delete                     SDelR         GET POST
@@ -67,7 +67,7 @@
     /sub/#CryptoFileNameSubmission SubmissionR !correctorANDisRead:
       /                           SubShowR                   GET POST !ownerANDtime !ownerANDisRead
       /archive/#{ZIPArchiveName SubmissionFileType} SubArchiveR                GET      !owner
-      /correction                 CorrectionR                GET POST !corrector !ownerANDisRead
+      /correction                 CorrectionR                GET POST !corrector !ownerANDisReadANDrated
       !/#SubmissionFileType/*FilePath SubDownloadR           GET      !owner
     /correctors                 SCorrR        GET POST
     !/#SheetFileType/*FilePath  SFileR        GET             !timeANDregistered !timeANDmaterials !corrector
diff --git a/shell.nix b/shell.nix
index 5185715fd..d305354a1 100644
--- a/shell.nix
+++ b/shell.nix
@@ -10,7 +10,7 @@ let
   drv = haskellPackages.callPackage ./uniworx.nix {};
 
   postgresSchema = pkgs.writeText "schema.sql" ''
-    CREATE USER uniworx;
+    CREATE USER uniworx WITH SUPERUSER;
     CREATE DATABASE uniworx_test;
     GRANT ALL ON DATABASE uniworx_test TO uniworx;
     CREATE DATABASE uniworx;
diff --git a/src/Application.hs b/src/Application.hs
index 4d9e54e11..aa4685549 100644
--- a/src/Application.hs
+++ b/src/Application.hs
@@ -98,7 +98,7 @@ makeFoundation appSettings@(AppSettings{..}) = do
         (pgPoolSize appDatabaseConf)
 
     -- Perform database migration using our application's logging settings.
-    runLoggingT (runSqlPool (runMigration migrateAll) pool) logFunc
+    runLoggingT (runSqlPool (runMigration $ migrateAll) pool) logFunc
 
     -- Return the foundation
     return $ mkFoundation pool
diff --git a/src/CryptoID.hs b/src/CryptoID.hs
index b8b4b2eed..3b5efceec 100644
--- a/src/CryptoID.hs
+++ b/src/CryptoID.hs
@@ -20,6 +20,7 @@ import CryptoID.TH
 import ClassyPrelude hiding (fromString)
 import Model
 
+import qualified Data.CryptoID as E
 import Data.CryptoID.Poly.ImplicitNamespace
 import Data.UUID.Cryptographic.ImplicitNamespace
 import System.FilePath.Cryptographic.ImplicitNamespace
@@ -39,7 +40,7 @@ instance PathPiece UUID where
 
 instance (CI.FoldCase s, PathPiece s) => PathPiece (CI s) where
   fromPathPiece = fmap CI.mk . fromPathPiece
-  toPathPiece = toPathPiece . CI.foldedCase
+  toPathPiece = toPathPiece . CI.original
 
 instance {-# OVERLAPS #-} PathMultiPiece FilePath where
   fromPathMultiPiece = Just . unpack . intercalate "/"
@@ -55,8 +56,12 @@ decCryptoIDs [ ''SubmissionId
              , ''FileId
              , ''UserId
              ]
-{- TODO: Do we need/want CryptoUUIDs for Sheet numbers? -}
 
+instance {-# OVERLAPS #-} namespace ~ CryptoIDNamespace (CI FilePath) SubmissionId => PathPiece (E.CryptoID namespace (CI FilePath)) where
+  fromPathPiece (Text.unpack -> piece) = do
+    piece' <- (stripPrefix `on` map CI.mk) "uwa" piece
+    return . CryptoID . CI.mk $ map CI.original piece'
+  toPathPiece = Text.pack . ("uwa" <>) . CI.foldedCase . ciphertext
 
 
 newtype SubmissionMode = SubmissionMode (Maybe CryptoFileNameSubmission)
diff --git a/src/Foundation.hs b/src/Foundation.hs
index 42fdbff39..b8f8fe169 100644
--- a/src/Foundation.hs
+++ b/src/Foundation.hs
@@ -9,9 +9,9 @@
 {-# LANGUAGE DataKinds #-}
 {-# LANGUAGE RecordWildCards #-}
 {-# LANGUAGE NamedFieldPuns #-}
-{-# LANGUAGE PatternGuards #-}
+{-# LANGUAGE PatternGuards, MultiWayIf #-}
 {-# LANGUAGE TupleSections #-}
-{-# LANGUAGE FlexibleInstances, UndecidableInstances #-}
+{-# LANGUAGE FlexibleInstances, UndecidableInstances, FlexibleContexts #-}
 
 module Foundation where
 
@@ -25,6 +25,8 @@ import Yesod.Auth.Message
 import Yesod.Auth.Dummy
 import Yesod.Auth.LDAP
 
+import qualified Network.Wai as W (requestMethod, pathInfo)
+
 import LDAP.Data (LDAPScope(..))
 import LDAP.Search (LDAPEntry(..))
 
@@ -35,14 +37,14 @@ import Data.CaseInsensitive (CI)
 import qualified Data.CaseInsensitive as CI
 import qualified Data.Text.Encoding as TE
 
+import qualified Data.CryptoID as E
+
 import Data.ByteArray (convert)
 import Crypto.Hash (Digest, SHAKE256)
 import Crypto.Hash.Conduit (sinkHash)
 
 import Yesod.Auth.Util.PasswordStore
 
-import qualified Data.CryptoID (CryptoID) -- for DisplayAble instance only
-
 import qualified Data.ByteString.Base64.URL as Base64 (encode)
 
 import Data.ByteString (ByteString)
@@ -58,6 +60,8 @@ import qualified Data.Set as Set
 import Data.Map (Map, (!?))
 import qualified Data.Map as Map
 
+import Data.Monoid (Any(..))
+
 
 import Data.Conduit (($$))
 import Data.Conduit.List (sourceList)
@@ -67,6 +71,9 @@ import qualified Database.Esqueleto as E
 import Control.Monad.Except (MonadError(..), runExceptT)
 import Control.Monad.Trans.Maybe (MaybeT(..))
 import Control.Monad.Trans.Reader (runReader)
+import Control.Monad.Trans.Writer (WriterT(..))
+import Control.Monad.Writer.Class (MonadWriter(..))
+import Control.Monad.Catch (handleAll)
 
 import System.FilePath
 
@@ -83,15 +90,15 @@ import qualified Data.Yaml as Yaml
 import Text.Shakespeare.Text (st)
 
 
+instance DisplayAble b => DisplayAble (E.CryptoID a b) where
+  display = display . ciphertext
+
+instance {-# OVERLAPS #-} namespace ~ CryptoIDNamespace (CI FilePath) SubmissionId => DisplayAble (E.CryptoID namespace (CI FilePath)) where
+  display = toPathPiece
 
--- -- TODO: Move the following to the appropriate place, if DisplayAble is kept
 instance DisplayAble TermId where
   display = termToText . unTermKey
 
-instance (PathPiece b) => DisplayAble (Data.CryptoID.CryptoID a b) where
-  display = toPathPiece -- requires import of Data.CryptoID here
--- -- MOVE ABOVE
-
 
 -- infixl 9 :$:
 -- pattern a :$: b = a b
@@ -170,6 +177,15 @@ instance RenderMessage UniWorX TermIdentifier where
     Winter -> renderMessage' $ MsgWinterTerm year
     where renderMessage' = renderMessage foundation ls
 
+newtype ShortTermIdentifier = ShortTermIdentifier TermIdentifier
+  deriving (Eq, Ord, Read, Show)
+
+instance RenderMessage UniWorX ShortTermIdentifier where
+  renderMessage foundation ls (ShortTermIdentifier TermIdentifier{..}) = case season of
+    Summer -> renderMessage' $ MsgSummerTermShort year
+    Winter -> renderMessage' $ MsgWinterTermShort year
+    where renderMessage' = renderMessage foundation ls
+
 instance RenderMessage UniWorX String where
   renderMessage f ls str = renderMessage f ls $ Text.pack str
 
@@ -181,6 +197,9 @@ instance RenderMessage UniWorX SheetFileType where
       SheetMarking  -> renderMessage' MsgSheetMarking
     where renderMessage' = renderMessage foundation ls
 
+instance RenderMessage UniWorX (UnsupportedAuthPredicate (Route UniWorX)) where
+  renderMessage f ls (UnsupportedAuthPredicate tag route) = renderMessage f ls $ MsgUnsupportedAuthPredicate tag (show route)
+
 getTimeLocale' :: [Lang] -> TimeLocale
 getTimeLocale' = $(timeLocaleMap [("de", "de_DE.utf8")])
 
@@ -341,9 +360,7 @@ knownTags = Map.fromList -- should not throw exceptions, i.e. no getBy404 or req
              && NTop courseRegisterTo   >= cTime
         return Authorized
 
-      r -> do
-         $logErrorS "AccessControl" $ "'!time' used on route that doesn't support it: " <> tshow r
-         unauthorizedI MsgUnauthorized
+      r -> $unsupportedAuthPredicate "time" r
    )
   ,("registered", APDB $ \route _ -> case route of
        CourseR tid csh _ -> exceptT return return $ do
@@ -356,9 +373,7 @@ knownTags = Map.fromList -- should not throw exceptions, i.e. no getBy404 or req
            return (E.countRows :: E.SqlExpr (E.Value Int64))
          guardMExceptT (c > 0) (unauthorizedI MsgUnauthorizedParticipant)
          return Authorized
-       r -> do
-         $logErrorS "AccessControl" $ "'!registered' used on route that doesn't support it: " <> tshow r
-         unauthorizedI MsgUnauthorized
+       r -> $unsupportedAuthPredicate "registered" r
    )
   ,("capacity", APDB $ \route _ -> case route of
        CourseR tid csh _ -> maybeT (unauthorizedI MsgCourseNoCapacity) $ do
@@ -366,18 +381,14 @@ knownTags = Map.fromList -- should not throw exceptions, i.e. no getBy404 or req
          registered <- lift $ fromIntegral <$> count [ CourseParticipantCourse ==. cid ]
          guard $ NTop courseCapacity > NTop (Just registered)
          return Authorized
-       r -> do
-         $logErrorS "AccessControl" $ "'!capacity' used on route that doesn't support it: " <> tshow r
-         unauthorizedI MsgUnauthorized
+       r -> $unsupportedAuthPredicate "capacity" r
    )
   ,("materials", APDB $ \route _ -> case route of
       CourseR tid csh _ -> maybeT (unauthorizedI MsgUnfreeMaterials) $ do
         Entity _ Course{..} <- MaybeT . getBy $ CourseTermShort tid csh
         guard courseMaterialFree
         return Authorized
-      r -> do
-        $logErrorS "AccessControl" $ "'!materials' used on route that doesn't support it: " <> tshow r
-        unauthorizedI MsgUnauthorized
+      r -> $unsupportedAuthPredicate "materials" r
     )
   ,("owner", APDB $ \route _ -> case route of
        CSubmissionR _ _ _ cID _ -> exceptT return return $ do
@@ -385,9 +396,15 @@ knownTags = Map.fromList -- should not throw exceptions, i.e. no getBy404 or req
          authId <- maybeExceptT AuthenticationRequired $ lift maybeAuthId
          void . maybeMExceptT (unauthorizedI MsgUnauthorizedSubmissionOwner) . getBy $ UniqueSubmissionUser authId sid
          return Authorized
-       r -> do
-         $logErrorS "AccessControl" $ "'!owner' used on route that doesn't support it: " <> tshow r
-         unauthorizedI MsgUnauthorized
+       r -> $unsupportedAuthPredicate "owner" r
+   )
+  ,("rated", APDB $ \route _ -> case route of
+       CSubmissionR _ _ _ cID _ -> maybeT (unauthorizedI MsgUnauthorizedSubmissionRated) $ do
+         sid <- catchIfMaybeT (const True :: CryptoIDError -> Bool) $ decrypt cID
+         sub <- MaybeT $ get sid
+         guard $ submissionRatingDone sub
+         return Authorized
+       r -> $unsupportedAuthPredicate "rated" r
    )
   ,("isRead",  APHandler . const $ bool (return Authorized) (unauthorizedI MsgUnauthorizedWrite))
   ,("isWrite", APHandler . const $ bool (unauthorizedI MsgUnauthorized) (return Authorized))
@@ -446,33 +463,53 @@ instance Yesod UniWorX where
     --   b) Validates that incoming write requests include that token in either a header or POST parameter.
     -- To add it, chain it together with the defaultMiddleware: yesodMiddleware = defaultYesodMiddleware . defaultCsrfMiddleware
     -- For details, see the CSRF documentation in the Yesod.Core.Handler module of the yesod-core package.
-    yesodMiddleware handler = do
-      void . runMaybeT $ do
-        route <- MaybeT getCurrentRoute
-        guardM . lift $ (== Authorized) <$> isAuthorized route False
-        case route of -- update Course Favourites here
-          CourseR tid csh _  -> do
-            uid <- MaybeT maybeAuthId
-            $(logDebug) "Favourites save"
-            now <- liftIO $ getCurrentTime
-            void . lift . runDB . runMaybeT $ do
-              cid  <- MaybeT . getKeyBy $ CourseTermShort tid csh
-              user <- MaybeT $ get uid
-              -- update Favourites
-              void . lift $ upsertBy
-                      (UniqueCourseFavourite uid cid)
-                      (CourseFavourite uid now cid)
-                      [CourseFavouriteTime =. now]
-              -- prune Favourites to user-defined size
-              oldFavs <- lift $ selectKeysList
-                                  [ CourseFavouriteUser ==. uid]
-                                  [ Desc CourseFavouriteTime
-                                  , OffsetBy $ userMaxFavourites user
-                                  ]
-              lift $ mapM_ delete oldFavs
+    yesodMiddleware = defaultYesodMiddleware . normalizeRouteMiddleware . defaultCsrfMiddleware . updateFavouritesMiddleware
+      where
+        updateFavouritesMiddleware :: Handler a -> Handler a
+        updateFavouritesMiddleware handler = (*> handler) . runMaybeT $ do
+          route <- MaybeT getCurrentRoute
+          case route of -- update Course Favourites here
+            CourseR tid csh _  -> do
+              void . lift . runDB . runMaybeT $ do
+                guardM . lift $ (== Authorized) <$> evalAccessDB (CourseR tid csh CShowR) False
+                $logDebugS "updateFavourites" "Updating favourites"
 
-          _other -> return ()
-      defaultYesodMiddleware handler -- handler is executed afterwards, so Favourites are updated immediately
+                now <- liftIO $ getCurrentTime
+                uid <- MaybeT $ liftHandlerT maybeAuthId
+                cid  <- MaybeT . getKeyBy $ CourseTermShort tid csh
+                user <- MaybeT $ get uid
+                let courseFavourite = CourseFavourite uid now cid
+    
+                $logDebugS "updateFavourites" [st|Updating/Inserting: #{tshow courseFavourite}|]
+                -- update Favourites
+                void . lift $ upsertBy
+                  (UniqueCourseFavourite uid cid)
+                  courseFavourite
+                  [CourseFavouriteTime =. now]
+                -- prune Favourites to user-defined size
+                oldFavs <- lift $ selectKeysList
+                  [ CourseFavouriteUser ==. uid]
+                  [ Desc CourseFavouriteTime
+                  , OffsetBy $ userMaxFavourites user
+                  ]
+                lift . forM_ oldFavs $ \fav -> do
+                  $logDebugS "updateFavourites" "Deleting old favourite."
+                  delete fav
+            _other -> return ()
+        normalizeRouteMiddleware :: Handler a -> Handler a
+        normalizeRouteMiddleware handler = (*> handler) . runMaybeT $ do
+          route <- MaybeT getCurrentRoute
+          (route', getAny -> changed) <- lift . runDB . runWriterT $ foldM (&) route routeNormalizers
+          when changed $ do
+            $logDebugS "normalizeRouteMiddleware" [st|Redirecting to #{tshow route'}|]
+            redirectWith movedPermanently301 route'
+
+    -- The following exception permits drive-by login via LDAP plugin. FIXME: Blocked by #17
+    isWriteRequest (AuthR (PluginR "LDAP" _)) = return False
+    isWriteRequest _ = do
+      wai <- waiRequest
+      return $ W.requestMethod wai `notElem`
+        ["GET", "HEAD", "OPTIONS", "TRACE"]
 
     defaultLayout widget = do
         master <- getYesod
@@ -629,18 +666,18 @@ instance YesodBreadcrumbs UniWorX where
   breadcrumb TermCurrentR           = return ("Aktuell"   , Just TermShowR)
   breadcrumb TermEditR              = return ("Neu"       , Just TermCurrentR)
   breadcrumb (TermEditExistR tid)   = return ("Editieren" , Just $ TermCourseListR tid)
-  breadcrumb (TermCourseListR term) = return (display term, Just TermShowR)
+  breadcrumb (TermCourseListR (unTermKey -> tid)) = getMessageRender <&> \mr -> (mr $ ShortTermIdentifier tid, Just TermShowR)
 
   breadcrumb  CourseListR                 = return ("Kurs"     , Just HomeR)
   breadcrumb  CourseNewR                  = return ("Neu"      , Just CourseListR)
-  breadcrumb (CourseR tid csh CShowR)     = return (csh        , Just $ TermCourseListR tid)
+  breadcrumb (CourseR tid csh CShowR)     = return (CI.original csh, Just $ TermCourseListR tid)
   --         (CourseR tid csh CRegisterR) -- is POST only
   breadcrumb (CourseR tid csh CEditR)     = return ("Editieren", Just $ CourseR tid csh CShowR)
   breadcrumb (CourseR tid csh CCorrectionsR) = return ("Abgaben",Just $ CourseR tid csh CShowR)
   breadcrumb (CourseR tid csh SheetListR) = return ("Übungen"  , Just $ CourseR tid csh CShowR)
   breadcrumb (CourseR tid csh SheetNewR ) = return ("Neu",       Just $ CourseR tid csh SheetListR)
 
-  breadcrumb (CSheetR tid csh shn SShowR) = return (shn,      Just $ CourseR tid csh SheetListR)
+  breadcrumb (CSheetR tid csh shn SShowR) = return (CI.original shn, Just $ CourseR tid csh SheetListR)
   breadcrumb (CSheetR tid csh shn SEditR) = return ("Edit",   Just $ CSheetR tid csh shn SShowR)
   breadcrumb (CSheetR tid csh shn SDelR ) = return ("DELETE", Just $ CSheetR tid csh shn SShowR)
   breadcrumb (CSheetR tid csh shn SSubsR) = return ("Abgaben", Just $ CSheetR tid csh shn SShowR)
@@ -657,7 +694,7 @@ instance YesodBreadcrumbs UniWorX where
   breadcrumb (CorrectionsUploadR) = return ("Hochladen", Just CorrectionsR)
   breadcrumb  _ = return ("Uni2work", Nothing) -- Default is no breadcrumb at all
 
-submissionList :: TermId -> Text -> Text -> UserId -> DB [E.Value SubmissionId]
+submissionList :: TermId -> CourseShorthand -> SheetName -> UserId -> DB [E.Value SubmissionId]
 submissionList tid csh shn uid = E.select . E.from $ \(course `E.InnerJoin` sheet `E.InnerJoin` submission `E.InnerJoin` submissionUser) -> do
   E.on $ submissionUser E.^. SubmissionUserSubmission E.==. submission E.^. SubmissionId
   E.on $ submission E.^. SubmissionSheet E.==. sheet E.^. SheetId
@@ -975,6 +1012,42 @@ pageHeading _
   = Nothing
 
 
+routeNormalizers :: [Route UniWorX -> WriterT Any (ReaderT (YesodPersistBackend UniWorX) (HandlerT UniWorX IO)) (Route UniWorX)]
+routeNormalizers =
+  [ normalizeRender
+  , ncCourse
+  , ncSheet
+  ]
+  where
+    normalizeRender route = route <$ do
+      YesodRequest{..} <- liftHandlerT getRequest
+      let original = (W.pathInfo reqWaiRequest, reqGetParams)
+          rendered = renderRoute route
+      if
+        | (isSuffixOf `on` fst) original rendered -> do -- FIXME: this breaks when subsite prefixes are dynamic
+            $logDebugS "normalizeRender" [st|#{tshow rendered} matches #{tshow original}|]
+        | otherwise -> do
+            $logDebugS "normalizeRender" [st|Redirecting because #{tshow rendered} does not match #{tshow original}|]
+            tell $ Any True
+    maybeOrig f route = maybeT (return route) $ f route
+    hasChanged a b
+      | ((/=) `on` CI.original) a b = do
+          $logDebugS "routeNormalizers" [st|#{tshow a} /= #{tshow b}|]
+          tell $ Any True
+      | otherwise                   = return ()
+    ncCourse = maybeOrig $ \route -> do
+      CourseR tid csh subRoute <- return route
+      Entity _ Course{..} <- MaybeT . lift . getBy $ CourseTermShort tid csh
+      hasChanged csh courseShorthand
+      return $ CourseR tid courseShorthand subRoute
+    ncSheet = maybeOrig $ \route -> do
+      CSheetR tid csh shn subRoute <- return route
+      Entity cid _ <- MaybeT . lift . getBy $ CourseTermShort tid csh
+      Entity _ Sheet{..} <- MaybeT . lift . getBy $ CourseSheet cid shn
+      hasChanged shn sheetName
+      return $ CSheetR tid csh sheetName subRoute
+
+  
 -- How to run database actions.
 instance YesodPersist UniWorX where
     type YesodPersistBackend UniWorX = SqlBackend
@@ -1021,7 +1094,7 @@ instance YesodAuth UniWorX where
         userEmail' = lookup "mail" credsExtra
         userDisplayName' = lookup "displayName" credsExtra
 
-      userEmail <- maybe (throwError $ ServerError "Could not retrieve user email") return userEmail'
+      userEmail <- maybe (throwError $ ServerError "Could not retrieve user email") (return . CI.mk) userEmail'
       userDisplayName <- maybe (throwError $ ServerError "Could not retrieve user name") return userDisplayName'
 
       AppSettings{..} <- getsYesod appSettings
diff --git a/src/Handler/Corrections.hs b/src/Handler/Corrections.hs
index a3bd66f5a..3d2a61116 100644
--- a/src/Handler/Corrections.hs
+++ b/src/Handler/Corrections.hs
@@ -75,68 +75,84 @@ sheetIs :: Key Sheet -> CorrectionsWhere
 sheetIs shid (_course,sheet,_submission) = sheet E.^. SheetId E.==. E.val shid
 
 
-type CorrectionTableData = DBRow (Entity Submission, Entity Sheet, (E.Value Text, E.Value Text, E.Value (Key Term), E.Value (Key School)), Maybe (Entity User))
+type CorrectionTableData = DBRow (Entity Submission, Entity Sheet, (CourseName, CourseShorthand, Key Term, Key School), Maybe (Entity User), Map UserId User)
 
 colTerm :: IsDBTable m a => Colonnade _ CorrectionTableData (DBCell m a)
 colTerm = sortable (Just "term") (i18nCell MsgTerm)
-        $ \DBRow{ dbrOutput=(_, _, course, _) } ->
+        $ \DBRow{ dbrOutput=(_, _, course, _, _) } ->
           -- cell [whamlet| _{untermKey $ course ^. _3}|]   -- lange, internationale Semester
-          textCell $ termToText $ unTermKey $ E.unValue $ course ^. _3 -- kurze Semsterkürzel
+          textCell $ termToText $ unTermKey $ course ^. _3 -- kurze Semsterkürzel
 
 colCourse :: IsDBTable m a => Colonnade _ CorrectionTableData (DBCell m a)
 colCourse = sortable (Just "course") (i18nCell MsgCourse)
-        $ \DBRow{ dbrOutput=(_, _, course, _) } -> cell $
-          let tid = E.unValue $ course ^. _3
-              csh = E.unValue $ course ^. _2
+        $ \DBRow{ dbrOutput=(_, _, course, _, _) } -> cell $
+          let tid = course ^. _3
+              csh = course ^. _2
           in [whamlet|<a href=@{CourseR tid csh CShowR}>#{display csh}|]
 
 colSheet :: IsDBTable m a => Colonnade _ CorrectionTableData (DBCell m a)
 colSheet = sortable (Just "sheet") (i18nCell MsgSheet)
-        $ \DBRow{ dbrOutput=(_, sheet, course, _) } -> cell $
-          let tid = E.unValue $ course ^. _3
-              csh = E.unValue $ course ^. _2
+        $ \DBRow{ dbrOutput=(_, sheet, course, _, _) } -> cell $
+          let tid = course ^. _3
+              csh = course ^. _2
               shn = sheetName $ entityVal sheet
           in [whamlet|<a href=@{CSheetR tid csh shn SShowR}>#{display shn}|]
           -- textCell $ sheetName $ entityVal sheet
 
 colCorrector :: IsDBTable m a => Colonnade _ CorrectionTableData (DBCell m a)
 colCorrector = sortable (Just "corrector") (i18nCell MsgCorrector) $ \case
-  DBRow{ dbrOutput = (_, _, _, Nothing) } -> cell mempty
-  DBRow{ dbrOutput = (_, _, _, Just corr) } -> textCell . display . userDisplayName $ entityVal corr
+  DBRow{ dbrOutput = (_, _, _, Nothing, _) } -> cell mempty
+  DBRow{ dbrOutput = (_, _, _, Just corr, _) } -> textCell . display . userDisplayName $ entityVal corr
 
 colSubmissionLink :: IsDBTable m a => Colonnade _ CorrectionTableData (DBCell m a)
 colSubmissionLink = sortable Nothing (i18nCell MsgSubmission)
-        $ \DBRow{ dbrOutput=(submission, sheet, course, _) } -> cell $ do
-          let tid = E.unValue $ course ^. _3
-              csh = E.unValue $ course ^. _2
+        $ \DBRow{ dbrOutput=(submission, sheet, course, _, _) } -> cell $ do
+          let tid = course ^. _3
+              csh = course ^. _2
               shn = sheetName $ entityVal sheet
           cid <- encrypt (entityKey submission :: SubmissionId)
           [whamlet|<a href=@{CSubmissionR tid csh shn cid SubShowR}>#{display cid}|]
 
 colSelect :: Colonnade _ CorrectionTableData (DBCell _ (FormResult (DBFormResult CorrectionTableData CryptoFileNameSubmission Bool)))
-colSelect = dbSelect id $ \DBRow{ dbrOutput=(Entity subId _, _, _, _) } -> encrypt subId
+colSelect = dbSelect id $ \DBRow{ dbrOutput=(Entity subId _, _, _, _, _) } -> encrypt subId
+
+colSubmittors :: IsDBTable m a => Colonnade _ CorrectionTableData (DBCell m a)
+colSubmittors = sortable Nothing (i18nCell MsgSubmissionUsers) $ \DBRow{ dbrOutput=(_, _, _, _, users) } -> let
+  cell = listCell (Map.toList users) $ \(userId, User{..}) -> anchorCellM (AdminUserR <$> encrypt userId) (toWidget userDisplayName)
+  in cell & cellAttrs <>~ [("class", "list--inline list--comma-separated")]
+  
 
 type CorrectionTableExpr = (E.SqlExpr (Entity Course) `E.InnerJoin` E.SqlExpr (Entity Sheet) `E.InnerJoin` E.SqlExpr (Entity Submission)) `E.LeftOuterJoin` E.SqlExpr (Maybe (Entity User))
             
 makeCorrectionsTable :: ( IsDBTable m x, ToSortable h, Functor h )
                      => _ -> Colonnade h CorrectionTableData (DBCell m x) -> PSValidator m x -> Handler (DBResult m x)
 makeCorrectionsTable whereClause colChoices psValidator = do
-  let tableData :: CorrectionTableExpr -> E.SqlQuery _
-      tableData ((course `E.InnerJoin` sheet `E.InnerJoin` submission) `E.LeftOuterJoin` corrector) = do
+  let dbtSQLQuery :: CorrectionTableExpr -> E.SqlQuery _
+      dbtSQLQuery ((course `E.InnerJoin` sheet `E.InnerJoin` submission) `E.LeftOuterJoin` corrector) = do
         E.on $ corrector E.?. UserId E.==. submission E.^. SubmissionRatingBy
         E.on $ sheet  E.^. SheetId  E.==. submission E.^. SubmissionSheet
         E.on $ course E.^. CourseId E.==. sheet      E.^. SheetCourse
         E.where_ $ whereClause (course,sheet,submission)
-        let crse =  ( course E.^. CourseName      :: E.SqlExpr (E.Value Text)
+        let crse =  ( course E.^. CourseName      :: E.SqlExpr (E.Value CourseName)
                     , course E.^. CourseShorthand
                     , course E.^. CourseTerm
                     , course E.^. CourseSchool    :: E.SqlExpr (E.Value SchoolId)
                     )
         return (submission, sheet, crse, corrector)
+      dbtProj :: DBRow _ -> MaybeT (ReaderT SqlBackend (HandlerT UniWorX IO)) CorrectionTableData
+      dbtProj = traverse $ \(submission@(Entity sId _), sheet, (E.Value courseName, E.Value courseShorthand, E.Value courseTerm, E.Value courseSchool), mCorrector) -> do
+        submittors <- lift . E.select . E.from $ \(submissionUser `E.InnerJoin` user) -> do
+          E.on $ submissionUser E.^. SubmissionUserUser E.==. user E.^. UserId
+          E.where_ $ submissionUser E.^. SubmissionUserSubmission E.==. E.val sId
+          E.orderBy [E.asc $ user E.^. UserId]
+          return user
+        let
+          submittorMap = foldr (\(Entity userId user) -> Map.insert userId user) Map.empty submittors
+        return (submission, sheet, (courseName, courseShorthand, courseTerm, courseSchool), mCorrector, submittorMap)
   dbTable psValidator $ DBTable
-    { dbtSQLQuery  = tableData
+    { dbtSQLQuery
     , dbtColonnade = colChoices
-    , dbtProj      = return 
+    , dbtProj
     , dbtSorting   = [ ( "term"
                        , SortColumn $ \((course `E.InnerJoin` _ `E.InnerJoin` _) `E.LeftOuterJoin` _) -> course E.^. CourseTerm
                        )
@@ -207,7 +223,7 @@ correctionsR whereClause (formColonnade -> displayColumns) psValidator actions =
     FormMissing      -> return ()
     FormSuccess (CorrDownloadData, subs) -> do
       ids <- Set.fromList <$> forM (Set.toList subs) decrypt -- Set is not traversable
-      addHeader "Content-Disposition" "attachment; filename=\"corrections.zip\""
+      addHeader "Content-Disposition" [st|attachment; filename="corrections.zip"|]
       sendResponse =<< submissionMultiArchive ids
     FormSuccess (CorrSetCorrectorData (Just uid), subs') -> do
       subs <- mapM decrypt $ Set.toList subs'
@@ -309,7 +325,7 @@ postCorrectionsR = do
     [ downloadAction
     ]
 
-getCCorrectionsR, postCCorrectionsR ::  TermId -> Text -> Handler TypedContent
+getCCorrectionsR, postCCorrectionsR ::  TermId -> CourseShorthand -> Handler TypedContent
 getCCorrectionsR = postCCorrectionsR
 postCCorrectionsR tid csh = do
   Entity cid _ <- runDB $ getBy404 $ CourseTermShort tid csh
@@ -319,6 +335,7 @@ postCCorrectionsR tid csh = do
         , dbRow
         , colSheet
         , colCorrector
+        , colSubmittors
         , colSubmissionLink
         ] -- Continue here
       psValidator = def
@@ -327,7 +344,7 @@ postCCorrectionsR tid csh = do
     , assignAction (Left cid)
     ]
 
-getSSubsR, postSSubsR :: TermId -> Text -> Text -> Handler TypedContent
+getSSubsR, postSSubsR :: TermId -> CourseShorthand -> SheetName -> Handler TypedContent
 getSSubsR = postSSubsR
 postSSubsR tid csh shn = do
   shid <- runDB $ fetchSheetId tid csh shn
@@ -336,6 +353,7 @@ postSSubsR tid csh shn = do
         [ colSelect
         , dbRow
         , colCorrector
+        , colSubmittors
         , colSubmissionLink
         ]
       psValidator = def
@@ -357,7 +375,7 @@ correctionData tid csh shn sub = E.select . E.from $ \((course `E.InnerJoin` she
 
   return (course, sheet, submission, corrector)
 
-getCorrectionR, getCorrectionUserR, postCorrectionR :: TermId -> Text -> Text -> CryptoFileNameSubmission -> Handler Html
+getCorrectionR, getCorrectionUserR, postCorrectionR :: TermId -> CourseShorthand -> SheetName -> CryptoFileNameSubmission -> Handler Html
 getCorrectionR tid csh shn cid = do
   mayPost <- isAuthorized (CSubmissionR tid csh shn cid CorrectionR) True
   bool getCorrectionUserR postCorrectionR (mayPost == Authorized) tid csh shn cid
@@ -371,7 +389,7 @@ postCorrectionR tid csh shn cid = do
       let ratingComment = fmap Text.strip submissionRatingComment >>= (\c -> c <$ guard (not $ null c))
 
       ((corrResult, corrForm), corrEncoding) <- runFormPost . identForm FIDcorrection . renderAForm FormStandard $ (,)
-        <$> aopt pointsField (fslI MsgRatingPoints) (Just $ submissionRatingPoints)
+        <$> aopt pointsField (fslpI MsgRatingPoints "Punktezahl" & setTooltip "Abgabe zählt als korrigiert, gdw. Punktezahl gesetzt ist") (Just $ submissionRatingPoints)
         <*> (((\t -> t <$ guard (not $ null t)) =<<) . fmap (Text.strip . unTextarea) <$> aopt textareaField (fslI MsgRatingComment) (Just $ Textarea <$> submissionRatingComment))
         <* submitButton
 
diff --git a/src/Handler/Course.hs b/src/Handler/Course.hs
index 5d3ee913c..38cfbe239 100644
--- a/src/Handler/Course.hs
+++ b/src/Handler/Course.hs
@@ -94,7 +94,7 @@ getTermCourseListR tid = do
     setTitleI . MsgTermCourseListTitle $ tid
     $(widgetFile "courses")
 
-getCShowR :: TermId -> Text -> Handler Html
+getCShowR :: TermId -> CourseShorthand -> Handler Html
 getCShowR tid csh = do
   mbAid <- maybeAuthId
   (courseEnt,(schoolMB,participants,registered)) <- runDB $ do
@@ -130,7 +130,7 @@ registerForm registered msecret extra = do
   return (btnRes *> ((==msecret) <$> msecretRes), widget) -- checks that correct button was pressed, and ignores result of btnRes
 
 
-postCRegisterR :: TermId -> Text -> Handler Html
+postCRegisterR :: TermId -> CourseShorthand -> Handler Html
 postCRegisterR tid csh = do
   aid <- requireAuthId
   (cid, course, registered) <- runDB $ do
@@ -159,12 +159,12 @@ getCourseNewR = do
 postCourseNewR :: Handler Html
 postCourseNewR = courseEditHandler False Nothing
 
-getCEditR :: TermId -> Text -> Handler Html
+getCEditR :: TermId -> CourseShorthand -> Handler Html
 getCEditR tid csh = do
   course <- runDB $ getBy $ CourseTermShort tid csh
   courseEditHandler True course
 
-postCEditR :: TermId -> Text -> Handler Html
+postCEditR :: TermId -> CourseShorthand -> Handler Html
 postCEditR tid csh = do
   course <- runDB $ getBy $ CourseTermShort tid csh
   courseEditHandler False course
@@ -255,8 +255,7 @@ courseEditHandler isGet course = do
 --                   else addMessageI "danger" $ MsgCourseEditDupShort tid csh
 
       (FormFailure _) -> addMessageI "warning" MsgInvalidInput
-      (FormMissing) | isGet -> return ()
-      other -> addMessage "error" $ [shamlet| Error: #{show other}|]
+      (FormMissing) -> return ()
     actionUrl <- fromMaybe CourseNewR <$> getCurrentRoute
     defaultLayout $ do
       setTitleI MsgCourseEditTitle
@@ -265,10 +264,10 @@ courseEditHandler isGet course = do
 
 data CourseForm = CourseForm
         { cfCourseId   :: Maybe CourseId -- Maybe CryptoUUIDCourse
-        , cfName       :: Text
+        , cfName       :: CourseName
         , cfDesc       :: Maybe Html
         , cfLink       :: Maybe Text
-        , cfShort      :: Text
+        , cfShort      :: CourseShorthand
         , cfTerm       :: TermId
         , cfSchool     :: SchoolId
         , cfCapacity   :: Maybe Int64
@@ -279,10 +278,6 @@ data CourseForm = CourseForm
         , cfDeRegUntil :: Maybe UTCTime
         }
 
-instance Show CourseForm where
-  show cf = T.unpack (cfShort cf) ++ ' ':(show $ cfCourseId cf)
-
-
 courseToForm :: Entity Course -> CourseForm
 courseToForm cEntity = CourseForm
         { cfCourseId   = Just $ entityKey cEntity
@@ -312,10 +307,10 @@ newCourseForm template = identForm FIDcourse $ \html -> do
     (result, widget) <- flip (renderAForm FormStandard) html $ CourseForm
       -- <$> pure cid -- $ join $ cfCourseId <$> template -- why doesnt this work?
       <$> aopt hiddenField "KursId"             (cfCourseId <$> template)
-      <*> areq textField (fsb "Name")           (cfName     <$> template)
+      <*> areq (ciField textField) (fsb "Name")           (cfName     <$> template)
       <*> aopt htmlField (fsb "Beschreibung")   (cfDesc     <$> template)
       <*> aopt urlField  (fsb "Homepage")       (cfLink     <$> template)
-      <*> areq textField (fsb "Kürzel"
+      <*> areq (ciField textField) (fsb "Kürzel"
             -- & addAttr "disabled" "disabled"
             & setTooltip "Muss innerhalb des Semesters eindeutig sein")
                                                 (cfShort  <$> template)
diff --git a/src/Handler/CryptoIDDispatch.hs b/src/Handler/CryptoIDDispatch.hs
index 32781c28d..6f198828b 100644
--- a/src/Handler/CryptoIDDispatch.hs
+++ b/src/Handler/CryptoIDDispatch.hs
@@ -21,7 +21,7 @@ import Import hiding (Proxy)
 
 import Data.Proxy
 
-import Handler.Utils
+import qualified Data.Text as Text
 
 import Yesod.Core.Types (HandlerContents(..), ErrorResponse(..))
 
@@ -46,14 +46,16 @@ instance CryptoRoute UUID SubmissionId where
     return $ CSubmissionR tid csh shn cID' SubShowR
 
 instance CryptoRoute (CI FilePath) SubmissionId where
-  cryptoIDRoute _ (CryptoID -> cID) = do
-    (smid :: SubmissionId) <- decrypt cID
-    (tid,csh,shn) <- runDB $ do
-      shid <- submissionSheet <$> get404 smid
-      Sheet{..}  <- get404 shid
-      Course{..} <- get404 sheetCourse
-      return (courseTerm, courseShorthand, sheetName)
-    return $ CSubmissionR tid csh shn cID SubShowR
+  cryptoIDRoute _ ciphertext
+    | Just cID <- fromPathPiece . Text.pack $ CI.original ciphertext = do
+        smid <- decrypt cID
+        (tid,csh,shn) <- runDB $ do
+          shid <- submissionSheet <$> get404 smid
+          Sheet{..}  <- get404 shid
+          Course{..} <- get404 sheetCourse
+          return (courseTerm, courseShorthand, sheetName)
+        return $ CSubmissionR tid csh shn cID SubShowR
+    | otherwise = notFound
 
 instance CryptoRoute UUID UserId where
   cryptoIDRoute _ (CryptoID -> cID) = do
diff --git a/src/Handler/Home.hs b/src/Handler/Home.hs
index 0448c1718..786828b70 100644
--- a/src/Handler/Home.hs
+++ b/src/Handler/Home.hs
@@ -115,8 +115,8 @@ homeUser uid = do
                    --                         (E.SqlExpr (Entity Course           )))
                    --                         (E.SqlExpr (Entity Sheet            ))
                 _ -> E.SqlQuery ( E.SqlExpr (E.Value (Key Term))
-                                , E.SqlExpr (E.Value Text)
-                                , E.SqlExpr (E.Value Text)
+                                , E.SqlExpr (E.Value CourseShorthand)
+                                , E.SqlExpr (E.Value SheetName)
                                 , E.SqlExpr (E.Value UTCTime)
                                 , E.SqlExpr (E.Value (Maybe SubmissionId)))
       tableData ((participant `E.InnerJoin` course `E.InnerJoin` sheet) `E.LeftOuterJoin` (submission `E.InnerJoin` subuser)) = do
@@ -138,8 +138,8 @@ homeUser uid = do
           )
 
       colonnade :: Colonnade Sortable (DBRow ( E.Value (Key Term)
-                                             , E.Value Text
-                                             , E.Value Text
+                                             , E.Value CourseShorthand
+                                             , E.Value SheetName
                                              , E.Value UTCTime
                                              , E.Value (Maybe SubmissionId)
                                              ))
diff --git a/src/Handler/Sheet.hs b/src/Handler/Sheet.hs
index 539ba05eb..64cc2a6b2 100644
--- a/src/Handler/Sheet.hs
+++ b/src/Handler/Sheet.hs
@@ -34,6 +34,9 @@ import Text.Blaze (text)
 import qualified Data.UUID.Cryptographic as UUID
 import qualified Data.Conduit.List as C
 
+import Data.CaseInsensitive (CI)
+import qualified Data.CaseInsensitive as CI
+
 import qualified Database.Esqueleto as E
 import qualified Database.Esqueleto.Internal.Sql as E
 
@@ -68,7 +71,7 @@ instance Eq (Unique Sheet) where
 -}
 
 data SheetForm = SheetForm
-      { sfName         :: Text
+      { sfName         :: SheetName
       , sfDescription  :: Maybe Html
       , sfType         :: SheetType
       , sfGrouping     :: SheetGroup
@@ -85,21 +88,23 @@ data SheetForm = SheetForm
       -- Keine SheetId im Formular!
       }
 
+getFtIdMap :: Key Sheet -> DB (SheetFileType -> Set FileId)
+getFtIdMap sId = do
+  allfIds <- E.select . E.from $ \(sheetFile `E.InnerJoin` file) -> do
+      E.on     $ sheetFile E.^. SheetFileFile  E.==. file E.^. FileId
+      E.where_ $ sheetFile E.^. SheetFileSheet E.==. E.val sId
+      return    (sheetFile E.^. SheetFileType, file E.^. FileId)
+  return $ partitionFileType [(t,i)|(E.Value t, E.Value i) <- allfIds]
 
 makeSheetForm :: Maybe SheetId -> Maybe SheetForm -> Form SheetForm
 makeSheetForm msId template = identForm FIDsheet $ \html -> do
-    -- TODO: SJ to refactor this; extract Code from getSEditR to joint code piece
-    let oldFileIds fType
-          | Just sId <- msId = fmap setFromList . fmap (map E.unValue) . runDB . E.select . E.from $ \(file `E.InnerJoin` sheetFile) -> do
-              E.on $ file E.^. FileId E.==. sheetFile E.^. SheetFileFile
-              E.where_ $ sheetFile E.^. SheetFileSheet E.==. E.val sId
-                   E.&&. sheetFile E.^. SheetFileType    E.==. E.val fType
-              return (file E.^. FileId)
-          | otherwise = return Set.empty
+    oldFileIds <- (return.) <$> case msId of
+      Nothing    -> return $ partitionFileType mempty
+      (Just sId) -> liftHandlerT $ runDB $ getFtIdMap sId
     mr <- getMsgRenderer
     ctime <- liftIO $ getCurrentTime
     (result, widget) <- flip (renderAForm FormStandard) html $ SheetForm
-      <$> areq textField      (fsb "Name")                     (sfName <$> template)
+      <$> areq (ciField textField) (fsb "Name") (sfName <$> template)
       <*> aopt htmlField      (fsb "Hinweise für Teilnehmer")  (sfDescription <$> template)
       <*> sheetTypeAFormReq   (fsb "Bewertung")                (sfType <$> template)
       <*> sheetGroupAFormReq  (fsb "Abgabegruppengröße") (sfGrouping <$> template)
@@ -149,7 +154,7 @@ makeSheetForm msId template = identForm FIDsheet $ \html -> do
         , ( NTop sfSolutionFrom >= NTop (Just sfActiveTo)   , render MsgSheetErrSolutionEarly)
       ] ]
 
-getSheetListR :: TermId -> Text -> Handler Html
+getSheetListR :: TermId -> CourseShorthand -> Handler Html
 getSheetListR tid csh = do
   Entity cid _ <- runDB . getBy404 $ CourseTermShort tid csh
   let
@@ -206,7 +211,7 @@ getSheetListR tid csh = do
 
 
 -- Show single sheet
-getSShowR :: TermId -> Text -> Text -> Handler Html
+getSShowR :: TermId -> CourseShorthand -> SheetName -> Handler Html
 getSShowR tid csh shn = do
   entSheet <- runDB $ fetchSheet tid csh shn
   let sheet = entityVal entSheet
@@ -265,16 +270,16 @@ getSShowR tid csh shn = do
     hasSolution <- (/= 0) <$> count [ SheetFileSheet ==. sid, SheetFileType ==. SheetSolution ]
     return (hasHints, hasSolution)
   defaultLayout $ do
-    setTitle $ toHtml $ T.append "Übung " $ sheetName sheet
+    setTitleI $ MsgSheetTitle tid csh shn
     sheetFrom <- formatTime SelFormatDateTime $ sheetActiveFrom sheet
     sheetTo <- formatTime SelFormatDateTime $ sheetActiveTo sheet
     hintsFrom <- traverse (formatTime SelFormatDateTime) $ sheetHintFrom sheet
     solutionFrom <- traverse (formatTime SelFormatDateTime) $ sheetSolutionFrom sheet
     $(widgetFile "sheetShow")
 
-getSFileR :: TermId -> Text -> Text -> SheetFileType -> FilePath -> Handler TypedContent
+getSFileR :: TermId -> CourseShorthand -> SheetName -> SheetFileType -> FilePath -> Handler TypedContent
 getSFileR tid csh shn typ title = do
-  content <- runDB $ E.select $ E.from $
+  results <- runDB $ E.select $ E.from $
     \(course `E.InnerJoin` sheet `E.InnerJoin` sheetFile `E.InnerJoin` file) -> do
       -- Restrict to consistent rows that correspond to each other
       E.on (file      E.^. FileId           E.==. sheetFile E.^. SheetFileFile)
@@ -288,38 +293,36 @@ getSFileR tid csh shn typ title = do
         E.&&.   (course    E.^. CourseTerm    E.==. E.val tid  )
         )
       -- return desired columns
-      return $ file E.^. FileContent
+      return $ (file E.^. FileTitle, file E.^. FileContent)
   let mimeType = defaultMimeLookup $ pack title
-  case content of
-    [E.Value (Just nochmalContent)] -> do
-      addHeader "Content-Disposition" "attachment"
-      respond mimeType nochmalContent
-    []     -> notFound
-    _other -> error "Multiple matching files found."
+  case results of
+    [(E.Value fileTitle, E.Value fileContent)]
+      | Just fileContent' <- fileContent -> do
+          addHeader "Content-Disposition" [st|attachment; filename="#{takeFileName fileTitle}"|]
+          return $ TypedContent (defaultMimeLookup (pack fileTitle) <> "; charset=utf-8") (toContent fileContent')
+      | otherwise -> sendResponseStatus noContent204 ()
+    [] -> notFound
+    other -> do
+      $logErrorS "SFileR" $ "Multiple matching files: " <> tshow other
+      error "Multiple matching files found."
 
-
-getSheetNewR :: TermId -> Text -> Handler Html
+getSheetNewR :: TermId -> CourseShorthand -> Handler Html
 getSheetNewR tid csh = do
   let template = Nothing -- TODO: provide convenience by interpolating name/nr/dates+7days
   let action newSheet = -- More specific error message for new sheet could go here, if insertUnique returns Nothing
         insertUnique $ newSheet
   handleSheetEdit tid csh Nothing template action
 
-postSheetNewR :: TermId -> Text -> Handler Html
+postSheetNewR :: TermId -> CourseShorthand -> Handler Html
 postSheetNewR = getSheetNewR
 
 
-getSEditR :: TermId -> Text -> Text -> Handler Html
+getSEditR :: TermId -> CourseShorthand -> SheetName -> Handler Html
 getSEditR tid csh shn = do
   (sheetEnt, sheetFileIds) <- runDB $ do
     ent <- fetchSheet tid csh shn
-    allfIds <- E.select . E.from $ \(file `E.InnerJoin` sheetFile) -> do
-      E.on $ file E.^. FileId E.==. sheetFile E.^. SheetFileFile
-      E.where_ $ sheetFile E.^. SheetFileSheet E.==. E.val (entityKey ent)
-      return (sheetFile E.^. SheetFileType, file E.^. FileId)
-    let ftIds :: SheetFileType -> Set FileId
-        ftIds ft = Set.fromList $ mapMaybe (\(E.Value t, E.Value i) -> i <$ guard (ft==t)) allfIds
-    return (ent, ftIds)
+    fti <- getFtIdMap $ entityKey ent
+    return (ent, fti)
   let sid = entityKey sheetEnt
   let oldSheet@(Sheet {..}) = entityVal sheetEnt
   let template = Just $ SheetForm
@@ -345,10 +348,10 @@ getSEditR tid csh shn = do
           (Just _err) -> return $ Nothing -- More specific error message for edit old sheet could go here
   handleSheetEdit tid csh (Just sid) template action
 
-postSEditR :: TermId -> Text -> Text -> Handler Html
+postSEditR :: TermId -> CourseShorthand -> SheetName -> Handler Html
 postSEditR = getSEditR
 
-handleSheetEdit :: TermId -> Text -> Maybe SheetId -> Maybe SheetForm -> (Sheet -> YesodDB UniWorX (Maybe SheetId)) -> Handler Html
+handleSheetEdit :: TermId -> CourseShorthand -> Maybe SheetId -> Maybe SheetForm -> (Sheet -> YesodDB UniWorX (Maybe SheetId)) -> Handler Html
 handleSheetEdit tid csh msId template dbAction = do
   let mbshn  = sfName <$> template
   aid  <- requireAuthId
@@ -396,7 +399,7 @@ handleSheetEdit tid csh msId template dbAction = do
 
 
 
-getSDelR :: TermId -> Text -> Text -> Handler Html
+getSDelR :: TermId -> CourseShorthand -> SheetName -> Handler Html
 getSDelR tid csh shn = do
   ((result,formWidget), formEnctype) <- runFormPost (buttonForm :: Form BtnDelete)
   case result of
@@ -417,7 +420,7 @@ getSDelR tid csh shn = do
         setTitleI $ MsgSheetTitle tid csh shn
         $(widgetFile "formPageI18n")
 
-postSDelR :: TermId -> Text -> Text -> Handler Html
+postSDelR :: TermId -> CourseShorthand -> SheetName -> Handler Html
 postSDelR = getSDelR
 
 
@@ -505,8 +508,8 @@ correctorForm shid = do
 
   (countTutRes, countTutView) <- mreq checkBoxField (fsm MsgCountTutProp) . Just $ any (\Load{..} -> fromMaybe False byTutorial) $ Map.elems loads'
   let
-    tutorField :: Field Handler [Text]
-    tutorField = multiEmailField
+    tutorField :: Field Handler [UserEmail]
+    tutorField = convertField (map CI.mk) (map CI.original) $ multiEmailField
       { fieldView = \theId name attrs val isReq -> asWidgetT $ do
           listIdent <- newIdent
           userId <- handlerToWidget requireAuthId
@@ -616,10 +619,7 @@ correctorForm shid = do
   -- Eingabebox für Korrektor hinzufügen
   -- Eingabe für Korrekt ausgefüllt: FormMissing zurückschicken um dann Feld hinzuzufügen
 
-getSCorrR, postSCorrR :: TermId
-                      -> Text -- ^ Course shorthand
-                      -> Text -- ^ Sheet name
-                      -> Handler Html
+getSCorrR, postSCorrR :: TermId -> CourseShorthand -> SheetName -> Handler Html
 postSCorrR = getSCorrR
 getSCorrR tid csh shn = do
   Entity shid Sheet{..} <- runDB $ fetchSheet tid csh shn
diff --git a/src/Handler/Submission.hs b/src/Handler/Submission.hs
index 8b71cbefb..73f68f988 100644
--- a/src/Handler/Submission.hs
+++ b/src/Handler/Submission.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE RecordWildCards #-}
+{-# LANGUAGE RecordWildCards, NamedFieldPuns #-}
 {-# LANGUAGE NoImplicitPrelude #-}
 {-# LANGUAGE OverloadedStrings #-}
 {-# LANGUAGE OverloadedLists #-}
@@ -56,18 +56,16 @@ import Colonnade hiding (bool, fromMaybe)
 import qualified Yesod.Colonnade as Yesod
 import qualified Text.Blaze.Html5.Attributes as HA
 
-import Text.Shakespeare.Text (st)
-
 
 numberOfSubmissionEditDates :: Int64
 numberOfSubmissionEditDates = 3 -- for debugging only, should be 1 in production.
 
 
-makeSubmissionForm :: Maybe SubmissionId -> Bool -> SheetGroup -> [Text] -> Form (Maybe (Source Handler File), [Text])
+makeSubmissionForm :: Maybe SubmissionId -> Bool -> SheetGroup -> [UserEmail] -> Form (Maybe (Source Handler File), [UserEmail])
 makeSubmissionForm msmid unpackZips grouping buddies = identForm FIDsubmission $ \html -> do
     flip (renderAForm FormStandard) html $ (,)
       <$> (bool (\f fs _ -> Just <$> areq f fs Nothing) aopt $ isJust msmid) (zipFileField unpackZips) (fsm $ bool MsgSubmissionFile MsgSubmissionArchive unpackZips) Nothing
-      <*> (catMaybes <$> sequenceA [bool aforced' aopt editableBuddies textField (fslpI (MsgSubmissionMember g) "user@campus.lmu.de" ) buddy
+      <*> (catMaybes <$> sequenceA [bool aforced' aopt editableBuddies (ciField textField) (fslpI (MsgSubmissionMember g) "user@campus.lmu.de" ) buddy
                                     | g <- [1..(max groupNr $ length buddies)]             -- groupNr might have decreased meanwhile
                                     | buddy <- map (Just . Just) buddies ++ repeat Nothing -- show current buddies
                                     ])
@@ -80,16 +78,16 @@ makeSubmissionForm msmid unpackZips grouping buddies = identForm FIDsubmission $
     aforced' f fs (Just (Just v)) = Just <$> aforced f fs v
     aforced' _ _  _ = error "Cannot happen since groupNr==0 if grouping/=Arbitrary"
 
-getSubmissionNewR, postSubmissionNewR :: TermId -> Text -> Text -> Handler Html
+getSubmissionNewR, postSubmissionNewR :: TermId -> CourseShorthand -> SheetName -> Handler Html
 getSubmissionNewR = postSubmissionNewR
 postSubmissionNewR tid csh shn = submissionHelper tid csh shn NewSubmission
 
 
-getSubShowR, postSubShowR :: TermId -> Text -> Text -> CryptoFileNameSubmission -> Handler Html
+getSubShowR, postSubShowR :: TermId -> CourseShorthand -> SheetName -> CryptoFileNameSubmission -> Handler Html
 getSubShowR = postSubShowR
 postSubShowR tid csh shn cid = submissionHelper tid csh shn $ ExistingSubmission cid
 
-getSubmissionOwnR :: TermId -> Text -> Text -> Handler Html
+getSubmissionOwnR :: TermId -> CourseShorthand -> SheetName -> Handler Html
 getSubmissionOwnR tid csh shn = do
   authId <- requireAuthId
   sid <- runDB $ do
@@ -105,7 +103,7 @@ getSubmissionOwnR tid csh shn = do
   cID <- encrypt sid
   redirect $ CSubmissionR tid csh shn cID SubShowR
 
-submissionHelper :: TermId -> Text -> Text -> SubmissionMode -> Handler Html
+submissionHelper :: TermId -> CourseShorthand -> SheetName -> SubmissionMode -> Handler Html
 submissionHelper tid csh shn (SubmissionMode mcid) = do
   uid   <- requireAuthId
   msmid <- traverse decrypt mcid
@@ -143,7 +141,7 @@ submissionHelper tid csh shn (SubmissionMode mcid) = do
             addMessageI "info" $ MsgSubmissionAlreadyExists
             redirect $ CSubmissionR tid csh shn cID SubShowR
       (Just smid) -> do
-        submissionMatchesSheet tid csh shn (fromJust mcid)
+        void $ submissionMatchesSheet tid csh shn (fromJust mcid)
         
         shid' <- submissionSheet <$> get404 smid
         -- fetch buddies from current submission
@@ -169,14 +167,13 @@ submissionHelper tid csh shn (SubmissionMode mcid) = do
       (FormMissing )           -> return $ FormMissing
       (FormFailure failmsgs)   -> return $ FormFailure failmsgs
       (FormSuccess (mFiles,[])) -> return $ FormSuccess (mFiles,[]) -- Type change
-      (FormSuccess (mFiles, (map CI.mk -> gEMails@(_:_)))) -- Validate AdHoc Group Members
+      (FormSuccess (mFiles,gEMails@(_:_))) -- Validate AdHoc Group Members
         | (Arbitrary {..}) <- sheetGrouping -> do
           -- , length gEMails < maxParticipants -> do -- < since submitting user is already accounted for
-          let gemails = map CI.foldedCase gEMails
-              prep :: [(E.Value Text, (E.Value UserId, E.Value Bool, E.Value Bool))] -> Map (CI Text) (Maybe (UserId, Bool, Bool))
-              prep ps = Map.filter (maybe True $ \(i,_,_) -> i /= uid) . Map.fromList $ map (, Nothing) gEMails ++ [(CI.mk m, Just (i,p,s))|(E.Value m, (E.Value i, E.Value p, E.Value s)) <- ps]
+          let prep :: [(E.Value UserEmail, (E.Value UserId, E.Value Bool, E.Value Bool))] -> Map (CI Text) (Maybe (UserId, Bool, Bool))
+              prep ps = Map.filter (maybe True $ \(i,_,_) -> i /= uid) . Map.fromList $ map (, Nothing) gEMails ++ [(m, Just (i,p,s))|(E.Value m, (E.Value i, E.Value p, E.Value s)) <- ps]
           participants <- fmap prep . E.select . E.from $ \user -> do
-            E.where_ $ (E.lower_ $ user E.^. UserEmail) `E.in_` E.valList gemails
+            E.where_ $ (user E.^. UserEmail) `E.in_` E.valList gEMails
             let
               isParticipant = E.sub_select . E.from $ \courseParticipant -> do
                 E.where_ $ user E.^. UserId E.==. courseParticipant E.^. CourseParticipantUser
@@ -198,9 +195,9 @@ submissionHelper tid csh shn (SubmissionMode mcid) = do
           let
             failmsgs = (concat :: [[Text]] -> [Text])
               [ flip Map.foldMapWithKey participants $ \email -> \case
-                  Nothing            -> pure . mr $ MsgEMailUnknown $ CI.original email
-                  (Just (_,False,_)) -> pure . mr $ MsgNotAParticipant (CI.original email) tid csh
-                  (Just (_,_, True)) -> pure . mr $ MsgSubmissionAlreadyExistsFor (CI.original email)
+                  Nothing            -> pure . mr $ MsgEMailUnknown email
+                  (Just (_,False,_)) -> pure . mr $ MsgNotAParticipant email tid csh
+                  (Just (_,_, True)) -> pure . mr $ MsgSubmissionAlreadyExistsFor email
                   _other             -> mempty
               , case length participants `compare` maxParticipants of
                   LT -> mempty
@@ -309,42 +306,54 @@ submissionHelper tid csh shn (SubmissionMode mcid) = do
     $(widgetFile "submission")
 
 
-getSubDownloadR :: TermId -> Text -> Text -> CryptoFileNameSubmission -> SubmissionFileType -> FilePath -> Handler TypedContent
+getSubDownloadR :: TermId -> CourseShorthand -> SheetName -> CryptoFileNameSubmission -> SubmissionFileType -> FilePath -> Handler TypedContent
 getSubDownloadR tid csh shn cID (submissionFileTypeIsUpdate -> isUpdate) path = do
-  submissionID <- decrypt cID
-
   runDB $ do
-    submissionMatchesSheet tid csh shn cID
+    submissionID <- submissionMatchesSheet tid csh shn cID
 
     isRating <- maybe False (== submissionID) <$> isRatingFile path
+
+    when (isUpdate || isRating) $
+      guardAuthResult =<< evalAccessDB (CSubmissionR tid csh shn cID CorrectionR) False
+  
     case isRating of
-      True  -> do
-        file <- runMaybeT $ lift . ratingFile cID =<< MaybeT (getRating submissionID)
-        maybe notFound (return . toTypedContent . Text.decodeUtf8) $ fileContent =<< file
+      True
+        | isUpdate -> do
+            file <- runMaybeT $ lift . ratingFile cID =<< MaybeT (getRating submissionID)
+            maybe notFound (return . toTypedContent . Text.decodeUtf8) $ fileContent =<< file
+        | otherwise -> notFound
       False -> do
         results <- E.select . E.from $ \(sf `E.InnerJoin` f) -> do
           E.on (f E.^. FileId E.==. sf E.^. SubmissionFileFile)
           E.where_ $ sf E.^. SubmissionFileSubmission E.==. E.val submissionID
                E.&&. f E.^. FileTitle E.==. E.val path
-               E.&&. E.not_ (E.isNothing $ f E.^. FileContent)
                E.&&. E.not_ (sf E.^. SubmissionFileIsDeletion)
                E.&&. sf E.^. SubmissionFileIsUpdate E.==. E.val isUpdate
+               -- E.&&. E.not_ (E.isNothing $ f E.^. FileContent) -- This is fine, we just return 204
           return f
 
         let fileName = Text.pack $ takeFileName path
         case results of
-          [Entity _ File{ fileContent = Just c }] -> return $ TypedContent (defaultMimeLookup fileName <> "; charset=utf-8") (toContent c)
-          _ -> notFound
+          [Entity _ File{ fileContent = Just c, fileTitle }] -> do
+            addHeader "Content-Disposition" [st|attachment; filename="#{takeFileName fileTitle}"|]
+            return $ TypedContent (defaultMimeLookup (pack fileTitle) <> "; charset=utf-8") (toContent c)
+          [Entity _ File{ fileContent = Nothing }] -> sendResponseStatus noContent204 ()
+          other -> do
+            $logErrorS "SubDownloadR" $ "Multiple matching files: " <> tshow other
+            error "Multiple matching files found."
 
-getSubArchiveR :: TermId -> Text -> Text -> CryptoFileNameSubmission -> ZIPArchiveName SubmissionFileType -> Handler TypedContent
-getSubArchiveR tid csh shn cID@CryptoID{..} (ZIPArchiveName sfType) = do
-  submissionID <- decrypt cID
-
-  addHeader "Content-Disposition" [st|attachment; filename="#{toPathPiece cID}-#{toPathPiece sfType}.zip"|]
+getSubArchiveR :: TermId -> CourseShorthand -> SheetName -> CryptoFileNameSubmission -> ZIPArchiveName SubmissionFileType -> Handler TypedContent
+getSubArchiveR tid csh shn cID (ZIPArchiveName sfType) = do
+  when (sfType == SubmissionCorrected) $ 
+    guardAuthResult =<< evalAccess (CSubmissionR tid csh shn cID CorrectionR) False
 
+  let filename
+        | SubmissionOriginal <- sfType = ZIPArchiveName $ toPathPiece cID <> "-" <> toPathPiece sfType
+        | otherwise = ZIPArchiveName $ toPathPiece cID
+  
+  addHeader "Content-Disposition" [st|attachment; filename="#{toPathPiece filename}"|]
   respondSourceDB "application/zip" $ do
-    lift $ submissionMatchesSheet tid csh shn cID
-
+    submissionID <- lift $ submissionMatchesSheet tid csh shn cID
     rating <- lift $ getRating submissionID
 
     let
@@ -361,6 +370,6 @@ getSubArchiveR tid csh shn cID@CryptoID{..} (ZIPArchiveName sfType) = do
         when (sfType == SubmissionCorrected) $
           maybe (return ()) (yieldM . ratingFile cID) rating
 
-      zipComment = Text.encodeUtf8 . pack $ CI.foldedCase ciphertext
+      zipComment = Text.encodeUtf8 $ toPathPiece cID
 
     fileSource' .| produceZip ZipInfo{..} .| Conduit.map toFlushBuilder
diff --git a/src/Handler/Term.hs b/src/Handler/Term.hs
index 89547f436..20f12eaa3 100644
--- a/src/Handler/Term.hs
+++ b/src/Handler/Term.hs
@@ -44,7 +44,7 @@ getTermShowR = do
       let colonnadeTerms = widgetColonnade $ mconcat
             [ sortable Nothing "Kürzel" $
                 anchorCell' (\(Entity tid _, _) -> TermCourseListR tid)
-                            (\(Entity tid _, _) -> [whamlet|#{display tid}|])
+                            (\(Entity tid _, _) -> [whamlet|#{toPathPiece tid}|])
             , sortable (Just "lecture-start") (i18nCell MsgLectureStart) $ \(Entity _ Term{..},_) ->
                 cell $ formatTime SelFormatDate termLectureStart >>= toWidget
             , sortable (Just "lecture-end") "Ende Vorlesungen"   $ \(Entity _ Term{..},_) ->
diff --git a/src/Handler/Utils/Form.hs b/src/Handler/Utils/Form.hs
index 4c549109a..280f5dfa6 100644
--- a/src/Handler/Utils/Form.hs
+++ b/src/Handler/Utils/Form.hs
@@ -23,6 +23,9 @@ import Import
 import qualified Data.Char as Char
 import Data.String (IsString(..))
 
+import Data.CaseInsensitive (CI)
+import qualified Data.CaseInsensitive as CI
+
 import qualified Data.Foldable as Foldable
 
 -- import Yesod.Core
@@ -263,6 +266,8 @@ buttonForm csrf = do
 -- Fields --
 ------------
 
+ciField :: (Functor m, CI.FoldCase a) => Field m a -> Field m (CI a)
+ciField = convertField CI.mk CI.original
 
 natFieldI :: (Monad m, Integral i, RenderMessage (HandlerSite m) msg, RenderMessage (HandlerSite m) FormMessage) => msg -> Field m i
 natFieldI msg = checkBool (>= 0) msg intField
diff --git a/src/Handler/Utils/Rating.hs b/src/Handler/Utils/Rating.hs
index 2ec19d999..7702a7d52 100644
--- a/src/Handler/Utils/Rating.hs
+++ b/src/Handler/Utils/Rating.hs
@@ -66,8 +66,8 @@ instance Pretty x => Pretty (CI x) where
 
 
 data Rating = Rating
-  { ratingCourseName :: Text
-  , ratingSheetName :: Text
+  { ratingCourseName :: CourseName
+  , ratingSheetName :: SheetName
   , ratingCorrectorName :: Maybe Text
   , ratingSheetType :: SheetType
   , ratingValues :: Rating'
@@ -133,7 +133,7 @@ formatRating cID Rating{ ratingValues = Rating'{..}, ..} = let
       , ("Korrektor:" <+>) . pretty <$> ratingCorrectorName
       , Just $ "Bewertung:" <+> pretty (display ratingSheetType)
       ]
-    , "Abgabe-Id:" <+> pretty (ciphertext cID)
+    , "Abgabe-Id:" <+> pretty (Text.unpack $ toPathPiece cID)
     , "============================================="
     , "Bewertung:" <+> pretty ratingPoints
     , "=========== Beginn der Kommentare ==========="
@@ -145,7 +145,7 @@ ratingFile :: MonadIO m => CryptoFileNameSubmission -> Rating -> m File
 ratingFile cID rating@(Rating{ ratingValues = Rating'{..}, .. }) = do
   fileModified <- maybe (liftIO getCurrentTime) return ratingTime
   let
-    fileTitle = "bewertung_" <> (CI.foldedCase $ ciphertext (cID :: CryptoFileNameSubmission)) <.> "txt"
+    fileTitle = "bewertung_" <> (Text.unpack $ toPathPiece (cID :: CryptoFileNameSubmission)) <.> "txt"
     fileContent = Just . Lazy.ByteString.toStrict $ formatRating cID rating
   return File{..}
 
@@ -212,7 +212,8 @@ isRatingFile fName
 isRatingFile' :: FilePath -> Maybe CryptoFileNameSubmission
 isRatingFile' (takeFileName -> fName)
   | (bName, ".txt") <- splitExtension fName
-  , Just (CI.mk -> ciphertext) <- stripPrefix "bewertung_" bName
-  = Just CryptoID{..}
+  , Just piece <- stripPrefix "bewertung_" bName
+  , Just cID <- fromPathPiece $ Text.pack piece
+  = Just cID
   | otherwise
   = Nothing
diff --git a/src/Handler/Utils/Sheet.hs b/src/Handler/Utils/Sheet.hs
index 76fed4737..dbcd79dd9 100644
--- a/src/Handler/Utils/Sheet.hs
+++ b/src/Handler/Utils/Sheet.hs
@@ -24,7 +24,7 @@ fetchSheetAux ::  ( BaseBackend backend ~ SqlBackend
                   , PersistQueryRead backend, PersistUniqueRead backend
                   )
   =>  (E.SqlExpr (Entity Sheet) -> b)
-      -> TermId -> Text -> Text -> ReaderT backend m a
+      -> TermId -> CourseShorthand -> SheetName -> ReaderT backend m a
 fetchSheetAux prj tid csh shn =
     let cachId = encodeUtf8 $ tshow (tid,csh,shn)
     in  cachedBy cachId $ do
@@ -42,11 +42,11 @@ fetchSheetAux prj tid csh shn =
           [sheet] -> return sheet
           _other  -> notFound
 
-fetchSheet :: TermId -> Text -> Text -> YesodDB UniWorX (Entity Sheet)
+fetchSheet :: TermId -> CourseShorthand -> SheetName -> YesodDB UniWorX (Entity Sheet)
 fetchSheet = fetchSheetAux id
 
-fetchSheetId :: TermId -> Text -> Text -> YesodDB UniWorX (Key Sheet)
+fetchSheetId :: TermId -> CourseShorthand -> SheetName -> YesodDB UniWorX (Key Sheet)
 fetchSheetId tid cid shn = E.unValue <$> fetchSheetAux (E.^. SheetId) tid cid shn
 
-fetchSheetIdCourseId :: TermId -> Text -> Text -> YesodDB UniWorX (Key Sheet, Key Course)
+fetchSheetIdCourseId :: TermId -> CourseShorthand -> SheetName -> YesodDB UniWorX (Key Sheet, Key Course)
 fetchSheetIdCourseId tid cid shn = bimap E.unValue E.unValue <$> fetchSheetAux ((,) <$> (E.^. SheetId) <*> (E.^. SheetCourse)) tid cid shn
diff --git a/src/Handler/Utils/Submission.hs b/src/Handler/Utils/Submission.hs
index b09e57868..097a505d8 100644
--- a/src/Handler/Utils/Submission.hs
+++ b/src/Handler/Utils/Submission.hs
@@ -10,6 +10,7 @@
 {-# LANGUAGE DeriveGeneric, DeriveDataTypeable #-}
 {-# LANGUAGE TypeOperators #-}
 {-# LANGUAGE PartialTypeSignatures #-}
+{-# LANGUAGE FlexibleContexts #-}
 
 
 module Handler.Utils.Submission
@@ -43,6 +44,8 @@ import qualified Data.Set as Set
 import Data.Map (Map, (!?))
 import qualified Data.Map as Map
 
+import qualified Data.Text as Text
+
 import Data.CaseInsensitive (CI)
 import qualified Data.CaseInsensitive as CI
 
@@ -159,7 +162,7 @@ submissionMultiArchive (Set.toList -> ids) = do
         cID <- encrypt submissionID
 
         let
-          directoryName = CI.foldedCase $ ciphertext (cID :: CryptoFileNameSubmission)
+          directoryName = Text.unpack $ toPathPiece (cID :: CryptoFileNameSubmission)
               
           fileEntitySource = do
             submissionFileSource submissionID =$= Conduit.map entityVal
@@ -463,11 +466,7 @@ sinkMultiSubmission userId isUpdate = do
             Submission{..} <- get404 sId
             Sheet{..} <- get404 submissionSheet
             Course{..} <- get404 sheetCourse
-            authRes <- evalAccessDB (CSubmissionR courseTerm courseShorthand sheetName cID CorrectionR) True
-            case authRes of
-              AuthenticationRequired -> notAuthenticated
-              Unauthorized t -> permissionDenied t
-              Authorized -> return ()
+            guardAuthResult =<< evalAccessDB (CSubmissionR courseTerm courseShorthand sheetName cID CorrectionR) True
           return . newResumableSink $ sinkSubmission userId (Right sId) isUpdate
       sink' <- lift $ yield val ++$$ sink
       case sink' of
@@ -484,9 +483,11 @@ sinkMultiSubmission userId isUpdate = do
         acc (Just sId, fp) segment = return (Just sId, fp ++ [segment])
         acc (Nothing , fp) segment = do
           let
-            tryDecrypt ciphertext = do
-              sId <- decrypt (CryptoID (CI.mk segment) :: CryptoFileNameSubmission)
-              Just sId <$ get404 sId
+            tryDecrypt (Text.pack -> ciphertext)
+              | Just cID <- fromPathPiece ciphertext = do
+                  sId <- decrypt (cID :: CryptoFileNameSubmission)
+                  Just sId <$ get404 sId
+              | otherwise = return Nothing
           msId <- lift (lift $ tryDecrypt segment) `catches` [ E.Handler handleCryptoID, E.Handler (handleHCError $ Right fileTitle) ]
           return (msId, fp)
       (msId, (joinPath -> fileTitle')) <- foldM acc (Nothing, []) $ splitDirectories fileTitle
@@ -513,9 +514,10 @@ sinkMultiSubmission userId isUpdate = do
     handleCryptoID _ = return Nothing
     
 
-submissionMatchesSheet :: TermId -> Text -> Text -> CryptoFileNameSubmission -> DB ()
+submissionMatchesSheet :: TermId -> CourseShorthand -> SheetName -> CryptoFileNameSubmission -> DB SubmissionId
 submissionMatchesSheet tid csh shn cid = do
   sid <- decrypt cid
   shid <- fetchSheetId tid csh shn
   Submission{..} <- get404 sid
   when (shid /= submissionSheet) $ invalidArgsI [MsgSubmissionWrongSheet]
+  return sid
diff --git a/src/Handler/Utils/Table/Pagination.hs b/src/Handler/Utils/Table/Pagination.hs
index 26acd65dc..a7bda4a73 100644
--- a/src/Handler/Utils/Table/Pagination.hs
+++ b/src/Handler/Utils/Table/Pagination.hs
@@ -24,6 +24,7 @@ module Handler.Utils.Table.Pagination
   , DBRow(..)
   , DBStyle(..), DBEmptyStyle(..)
   , DBTable(..), IsDBTable(..), DBCell(..)
+  , cellAttrs, cellContents
   , PaginationSettings(..), PaginationInput(..), piIsUnset
   , PSValidator(..)
   , defaultFilter, defaultSorting
@@ -31,10 +32,13 @@ module Handler.Utils.Table.Pagination
   , ToSortable(..), Sortable(..), sortable
   , dbTable
   , widgetColonnade, formColonnade, dbColonnade
-  , textCell, stringCell, i18nCell, anchorCell, anchorCell', anchorCellM
+  , cell, textCell, stringCell, i18nCell
+  , anchorCell, anchorCell', anchorCellM
+  , listCell
   , formCell, DBFormResult, getDBFormResult
   , dbRow, dbSelect
   , (&)
+  , module Control.Monad.Trans.Maybe
   ) where
 
 import Handler.Utils.Table.Pagination.Types
@@ -59,6 +63,8 @@ import Control.Monad.Writer hiding ((<>), Foldable(..), mapM_, forM_)
 import Control.Monad.Reader (ReaderT(..), mapReaderT)
 import Control.Monad.Trans.Maybe
 
+import Data.Foldable (Foldable(foldMap))
+
 import Data.Map (Map, (!))
 import qualified Data.Map as Map
 
@@ -123,6 +129,15 @@ data DBRow r = DBRow
   , dbrIndex, dbrCount :: Int64
   } deriving (Show, Read, Eq, Ord)
 
+instance Functor DBRow where
+  fmap f DBRow{..} = DBRow{ dbrOutput = f dbrOutput, .. }
+
+instance Foldable DBRow where
+  foldMap f DBRow{..} = f dbrOutput
+
+instance Traversable DBRow where
+  traverse f DBRow{..} = DBRow <$> f dbrOutput <*> pure dbrIndex <*> pure dbrCount
+
 data DBEmptyStyle = DBESNoHeading | DBESHeading
   deriving (Enum, Bounded, Ord, Eq, Show, Read)
 
@@ -238,16 +253,19 @@ class (MonadHandler m, Monoid x, Monoid (DBCell m x)) => IsDBTable (m :: * -> *)
   -- type DBResult' m x :: *
 
   data DBCell m x :: *
-  cellAttrs :: Lens' (DBCell m x) [(Text, Text)]
-  cellContents :: DBCell m x -> WriterT x m Widget
-
-  cell :: Widget -> DBCell m x
+  dbCell :: Iso' (DBCell m x) ([(Text, Text)], WriterT x m Widget)
     
   -- dbWidget :: Proxy m -> Proxy x -> Iso' (DBResult m x) (Widget, DBResult' m x)
   dbWidget :: forall m'. (MonadHandler m', HandlerSite m' ~ UniWorX) => DBTable m x -> DBResult m x -> m' Widget
   dbHandler :: forall m'. (MonadHandler m' , HandlerSite m' ~ UniWorX) => DBTable m x -> (Widget -> Widget) -> DBResult m x -> m' (DBResult m x)
   runDBTable :: forall m'. (MonadHandler m', HandlerSite m' ~ UniWorX) => m (x, Widget) -> ReaderT SqlBackend m' (DBResult m x)
 
+cellAttrs :: IsDBTable m x => Lens' (DBCell m x) [(Text, Text)]
+cellAttrs = dbCell . _1
+
+cellContents :: IsDBTable m x => Lens' (DBCell m x) (WriterT x m Widget)
+cellContents = dbCell . _2
+
 instance IsDBTable (WidgetT UniWorX IO) () where
   type DBResult (WidgetT UniWorX IO) () = Widget
   -- type DBResult' (WidgetT UniWorX IO) () = ()
@@ -256,10 +274,10 @@ instance IsDBTable (WidgetT UniWorX IO) () where
     { wgtCellAttrs :: [(Text, Text)]
     , wgtCellContents :: Widget
     }
-  cellAttrs = lens wgtCellAttrs $ \w as -> w { wgtCellAttrs = as }
-  cellContents = return . wgtCellContents
 
-  cell = WidgetCell []
+  dbCell = iso
+    (\WidgetCell{..} -> (wgtCellAttrs, return wgtCellContents))
+    (\(attrs, mkWidget) -> WidgetCell attrs . join . fmap fst $ runWriterT mkWidget)
   
   -- dbWidget Proxy Proxy = iso (, ()) $ view _1
   dbWidget _ = return
@@ -278,10 +296,9 @@ instance IsDBTable (ReaderT SqlBackend (HandlerT UniWorX IO)) () where
     , dbCellContents :: ReaderT SqlBackend (HandlerT UniWorX IO) Widget
     }
 
-  cellAttrs = lens dbCellAttrs $ \w as -> w { dbCellAttrs = as }
-  cellContents = lift . dbCellContents
-
-  cell = DBCell [] . return
+  dbCell = iso
+    (\DBCell{..} -> (dbCellAttrs, lift dbCellContents))
+    (\(attrs, mkWidget) -> DBCell attrs . fmap fst $ runWriterT mkWidget)
 
   dbWidget _ = return
   dbHandler _ f x = return $ f x
@@ -301,10 +318,13 @@ instance Monoid a => IsDBTable (RWST (Maybe (Env, FileEnv), UniWorX, [Lang]) Enc
     { formCellAttrs :: [(Text, Text)]
     , formCellContents :: MForm (HandlerT UniWorX IO) (FormResult a, Widget)
     }
-  cellAttrs = lens formCellAttrs $ \w as -> w { formCellAttrs = as }
-  cellContents = WriterT . fmap swap . formCellContents
 
-  cell widget = FormCell [] $ return (mempty, widget)
+  -- dbCell :: Iso'
+  --             (DBCell (RWST ... ... ... (HandlerT UniWorX IO)) (FormResult a))
+  --             ([(Text, Text)], WriterT (FormResult a) (RWST ... ... ... (HandlerT UniWorX IO)) Widget)
+  dbCell = iso
+    (\FormCell{..} -> (formCellAttrs, WriterT $ fmap swap formCellContents))
+    (\(attrs, mkWidget) -> FormCell attrs . fmap swap $ runWriterT mkWidget)
   
   -- dbWidget Proxy Proxy = iso ((,) <$> view (_1._2) <*> ((,) <$> view (_1._1) <*> view _2))
   --                            ((,) <$> ((,) <$> view (_2._1) <*> view _1) <*> view (_2._2))
@@ -393,7 +413,7 @@ dbTable PSValidator{..} dbtable@(DBTable{ dbtIdent = (toPathPiece -> dbtIdent),
           tblLink f = decodeUtf8 . Builder.toLazyByteString . renderQueryText True $ f getParams
 
           genHeaders SortableP{..} = forM (toSortable . oneColonnadeHead <$> getColonnade dbtColonnade) $ \Sortable{..} -> do
-            widget <- cellContents sortableContent
+            widget <- sortableContent ^. cellContents
             let
               directions = [dir | (k, dir) <- psSorting, Just k == sortableKey ]
               isSortable = isJust sortableKey
@@ -407,7 +427,7 @@ dbTable PSValidator{..} dbtable@(DBTable{ dbtIdent = (toPathPiece -> dbtIdent),
         wHeaders <- maybe (return Nothing) (fmap Just . genHeaders) pSortable
 
         wRows <- forM rows $ \row -> forM (oneColonnadeEncode <$> getColonnade dbtColonnade) $ \(($ row) -> cell) -> do
-          widget <- cellContents cell
+          widget <- cell ^. cellContents
           let attrs = cell ^. cellAttrs
           return $(widgetFile "table/cell/body")
       
@@ -444,6 +464,9 @@ dbColonnade :: Headedness h
             -> Colonnade h r (DBCell (ReaderT SqlBackend (HandlerT UniWorX IO)) ())
 dbColonnade = id
 
+cell :: IsDBTable m a => Widget -> DBCell m a
+cell wgt = dbCell # ([], return wgt)
+
 textCell, stringCell, i18nCell :: (RenderMessage UniWorX msg, IsDBTable m a) => msg -> DBCell m a
 stringCell = textCell
 i18nCell = textCell
@@ -467,6 +490,12 @@ anchorCellM routeM widget = cell $ do
     | Authorized <- authResult -> $(widgetFile "table/cell/link")
     | otherwise                -> widget
 
+listCell :: (IsDBTable m a, Traversable f) => f r' -> (r' -> DBCell m a) -> DBCell m a
+listCell xs mkCell = review dbCell . ([], ) $ do
+  cells <- forM xs $
+    \(view dbCell . mkCell -> (attrs, mkWidget)) -> (attrs, ) <$> mkWidget
+  return $(widgetFile "table/cell/list")
+
 newtype DBFormResult r i a = DBFormResult (Map i (r, a -> a))
 
 instance Ord i => Monoid (DBFormResult r i a) where
diff --git a/src/Import/NoFoundation.hs b/src/Import/NoFoundation.hs
index 2e586ba56..665c509b5 100644
--- a/src/Import/NoFoundation.hs
+++ b/src/Import/NoFoundation.hs
@@ -19,3 +19,5 @@ import CryptoID               as Import
 import Data.UUID              as Import (UUID)
 
 import Text.Lucius            as Import
+
+import Text.Shakespeare.Text  as Import hiding (text, stext)
diff --git a/src/Model.hs b/src/Model.hs
index aef13b517..b810d9588 100644
--- a/src/Model.hs
+++ b/src/Model.hs
@@ -7,6 +7,7 @@
 {-# LANGUAGE OverloadedStrings          #-}
 {-# LANGUAGE TemplateHaskell            #-}
 {-# LANGUAGE TypeFamilies               #-}
+{-# LANGUAGE RecordWildCards            #-}
 module Model
   ( module Model
   , module Model.Types
@@ -14,20 +15,32 @@ module Model
 
 import ClassyPrelude.Yesod
 import Database.Persist.Quasi
+import Database.Persist.Postgresql (migrateEnableExtension)
+import Database.Persist.Sql (Migration)
 -- import Data.Time
 -- import Data.ByteString
 import Model.Types
 import Data.Aeson.TH
 
+import Data.CaseInsensitive (CI)
+
 -- You can define all of your database entities in the entities file.
 -- You can find more information on persistent and how to declare entities
 -- at:
 -- http://www.yesodweb.com/book/persistent/
-share [mkPersist sqlSettings, mkDeleteCascade sqlSettings, mkMigrate "migrateAll"]
+share [mkPersist sqlSettings, mkDeleteCascade sqlSettings, mkMigrate "migrateAll'"]
     $(persistFileWith lowerCaseSettings "models")
 
+migrateAll :: Migration
+migrateAll = do
+  migrateEnableExtension "citext"
+  migrateAll'
+
 data PWEntry = PWEntry
   { pwUser :: User
   , pwHash :: Text
   } deriving (Show)
 $(deriveJSON defaultOptions ''PWEntry)
+
+submissionRatingDone :: Submission -> Bool
+submissionRatingDone Submission{..} = isJust submissionRatingPoints
diff --git a/src/Model/Types.hs b/src/Model/Types.hs
index 8a2b908d7..bf035c79c 100644
--- a/src/Model/Types.hs
+++ b/src/Model/Types.hs
@@ -1,5 +1,6 @@
 {-# LANGUAGE RecordWildCards #-}
 {-# LANGUAGE PatternGuards #-}
+{-# LANGUAGE LambdaCase #-}
 {-# LANGUAGE TemplateHaskell #-}
 {-# LANGUAGE NoImplicitPrelude #-}
 {-# LANGUAGE OverloadedStrings #-}
@@ -7,14 +8,18 @@
 {-# LANGUAGE FlexibleInstances, MultiParamTypeClasses #-}
 {-# LANGUAGE ViewPatterns #-}
 {-- # LANGUAGE ExistentialQuantification #-} -- for DA type
+{-# OPTIONS_GHC -fno-warn-orphans #-}
 
 module Model.Types where
 
 import ClassyPrelude
 import Utils
+import Control.Lens
 
 import Data.Map (Map)
 import qualified Data.Map as Map
+import Data.Set (Set)
+import qualified Data.Set as Set
 import Data.Fixed
 
 import Database.Persist.TH
@@ -25,10 +30,11 @@ import Web.HttpApiData
 
 import Data.Text (Text)
 import qualified Data.Text as Text
+import qualified Data.Text.Encoding as Text
 
 import Text.Read (readMaybe,readsPrec)
 
--- import Data.CaseInsensitive (CI)
+import Data.CaseInsensitive (CI)
 import qualified Data.CaseInsensitive as CI
 
 import Yesod.Core.Dispatch (PathPiece(..))
@@ -38,6 +44,10 @@ import Data.Aeson.TH (deriveJSON, defaultOptions)
 import GHC.Generics (Generic)
 import Data.Typeable (Typeable)
 
+import Text.Shakespeare.I18N (ToMessage(..), RenderMessage(..))
+import Text.Blaze (ToMarkup(..))
+import Yesod.Core.Widget (ToWidget(..))
+
 
 type Points = Centi
 
@@ -95,6 +105,23 @@ instance DisplayAble SheetFileType where -- deprecated, see RenderMessage instan
   display SheetSolution = "Musterlösung"
   display SheetMarking  = "Korrekturhinweise"
 
+-- partitionFileType' :: Ord a => [(SheetFileType,a)] -> Map SheetFileType (Set a)
+-- partitionFileType' = groupMap
+
+partitionFileType :: Ord a => [(SheetFileType,a)] -> SheetFileType -> Set a
+partitionFileType fts =
+    let (se,sh,ss,sm) = foldl' switchft (Set.empty,Set.empty,Set.empty,Set.empty) fts
+    in \case  SheetExercise -> se
+              SheetHint     -> sh
+              SheetSolution -> ss
+              SheetMarking  -> sm
+  where
+    switchft :: Ord a => (Set a, Set a, Set a, Set a) -> (SheetFileType,a) -> (Set a, Set a, Set a, Set a)
+    switchft (se,sh,ss,sm) (SheetExercise,x) = (Set.insert x se, sh, ss, sm)
+    switchft (se,sh,ss,sm) (SheetHint    ,x) = (se, Set.insert x sh, ss, sm)
+    switchft (se,sh,ss,sm) (SheetSolution,x) = (se, sh, Set.insert x ss, sm)
+    switchft (se,sh,ss,sm) (SheetMarking ,x) = (se, sh, ss, Set.insert x sm)
+
 data SubmissionFileType = SubmissionOriginal | SubmissionCorrected
   deriving (Show, Read, Eq, Ord, Enum, Bounded)
 
@@ -178,17 +205,35 @@ data TermIdentifier = TermIdentifier
 -- from_TermId_to_TermIdentifier = unTermKey
 -- from_TermIdentifier_to_TermId = TermKey
 
-instance DisplayAble TermIdentifier where
-  display = termToText
+shortened :: Iso' Integer Integer
+shortened = iso shorten expand
+  where
+    century = ($currentYear `div` 100) * 100
+    expand year
+      | 0 <= year
+      , year < 100 = let
+          options = [ expanded | offset <- [-1, 0, 1]
+                               , let century' = century + offset * 100
+                                     expanded = century' + year
+                               , $currentYear - 50 <= expanded
+                               , expanded < $currentYear + 50
+                               ]
+          in case options of
+               [unique] -> unique
+               failed   -> error $ "Could not expand year " ++ show year ++ ": " ++ show failed
+      | otherwise = year
+    shorten year
+      | $currentYear - 50 <= year
+      , year < $currentYear + 50 = year `mod` 100
+      | otherwise = year
 
---TODO: Enforce the number of digits within year, with parsing filling in the current leading digits? Goal: short urls
 termToText :: TermIdentifier -> Text
-termToText TermIdentifier{..} = Text.pack $ seasonToChar season : show year
+termToText TermIdentifier{..} = Text.pack $ seasonToChar season : show (year ^. shortened)
 
 termFromText :: Text -> Either Text TermIdentifier
 termFromText t
   | (s:ys) <- Text.unpack t
-  , Just year <- readMaybe ys
+  , Just (review shortened -> year) <- readMaybe ys
   , Right season <- seasonFromChar s
   = Right TermIdentifier{..}
   | otherwise = Left $ "Invalid TermIdentifier: “" <> t <> "”"
@@ -297,3 +342,43 @@ newtype DateTimeFormat = DateTimeFormat { unDateTimeFormat :: String }
 
 data SelDateTimeFormat = SelFormatDateTime | SelFormatDate | SelFormatTime
   deriving (Eq, Ord, Read, Show, Enum, Bounded)
+
+
+instance PersistField (CI Text) where
+  toPersistValue ciText = PersistDbSpecific . Text.encodeUtf8 $ CI.original ciText
+  fromPersistValue (PersistDbSpecific bs) = Right . CI.mk $ Text.decodeUtf8 bs
+  fromPersistValue x = Left . pack $ "Expected PersistDbSpecific, received: " ++ show x
+
+instance PersistField (CI String) where
+  toPersistValue ciText = PersistDbSpecific . Text.encodeUtf8 . pack $ CI.original ciText
+  fromPersistValue (PersistDbSpecific bs) = Right . CI.mk . unpack $ Text.decodeUtf8 bs
+  fromPersistValue x = Left . pack $ "Expected PersistDbSpecific, received: " ++ show x
+  
+instance PersistFieldSql (CI Text) where
+  sqlType _ = SqlOther "citext"
+
+instance ToJSON a => ToJSON (CI a) where
+  toJSON = toJSON . CI.original
+
+instance (FromJSON a, CI.FoldCase a) => FromJSON (CI a) where
+  parseJSON = fmap CI.mk . parseJSON
+
+instance ToMessage a => ToMessage (CI a) where
+  toMessage = toMessage . CI.original
+
+instance ToMarkup a => ToMarkup (CI a) where
+  toMarkup = toMarkup . CI.original
+  preEscapedToMarkup = preEscapedToMarkup . CI.original
+
+instance ToWidget site a => ToWidget site (CI a) where
+  toWidget = toWidget . CI.original
+
+instance RenderMessage site a => RenderMessage site (CI a) where
+  renderMessage f ls msg = renderMessage f ls $ CI.original msg
+
+-- Type synonyms
+
+type SheetName = CI Text
+type CourseShorthand = CI Text
+type CourseName = CI Text
+type UserEmail = CI Text
diff --git a/src/Utils.hs b/src/Utils.hs
index 1ec44e5ba..36412836a 100644
--- a/src/Utils.hs
+++ b/src/Utils.hs
@@ -4,7 +4,8 @@
 {-# LANGUAGE RankNTypes #-}
 {-# LANGUAGE TypeSynonymInstances, FlexibleInstances, UndecidableInstances #-}
 {-# LANGUAGE TypeFamilies, FlexibleContexts, ConstraintKinds #-}
-{-# LANGUAGE QuasiQuotes #-}
+{-# LANGUAGE QuasiQuotes, TemplateHaskell #-}
+{-# LANGUAGE ViewPatterns #-}
 {-# OPTIONS_GHC -fno-warn-orphans #-} -- Monad FormResult
 
 module Utils
@@ -17,14 +18,19 @@ import Data.List (foldl)
 import Data.Foldable as Fold
 import qualified Data.Char as Char
 
+import Data.CaseInsensitive (CI)
+import qualified Data.CaseInsensitive as CI
+
 import Utils.DB as Utils
 import Utils.Common as Utils
 import Utils.DateTime as Utils
 
 import Text.Blaze (Markup, ToMarkup)
 
--- import Data.Map (Map)
--- import qualified Data.Map as Map
+import Data.Set (Set)
+import qualified Data.Set as Set
+import Data.Map (Map)
+import qualified Data.Map as Map
 -- import qualified Data.List as List
 
 import Control.Monad.Trans.Except (ExceptT(..), throwE, runExceptT)
@@ -34,6 +40,11 @@ import Control.Monad.Catch
 
 import qualified Database.Esqueleto as E (Value, unValue)
 
+import Language.Haskell.TH
+import Instances.TH.Lift ()
+
+import Text.Shakespeare.Text (st)
+
 -----------
 -- Yesod --
 -----------
@@ -51,6 +62,22 @@ instance Monad FormResult where
   (FormFailure errs) >>= _ = FormFailure errs
   (FormSuccess a)    >>= f = f a
 
+guardAuthResult :: MonadHandler m => AuthResult -> m ()
+guardAuthResult AuthenticationRequired = notAuthenticated
+guardAuthResult (Unauthorized t) = permissionDenied t
+guardAuthResult Authorized = return ()
+
+data UnsupportedAuthPredicate route = UnsupportedAuthPredicate String route
+  deriving (Eq, Ord, Typeable, Show)
+instance (Show route, Typeable route) => Exception (UnsupportedAuthPredicate route)
+
+unsupportedAuthPredicate :: ExpQ
+unsupportedAuthPredicate = do
+  logFunc <- logErrorS
+  [e| \tag route -> do
+        $(return logFunc) "AccessControl" [st|"!#{tag}" used on route that doesn't support it: #{tshow route}|]
+        unauthorizedI (UnsupportedAuthPredicate tag route)
+    |]
 
 
 ---------------------
@@ -116,6 +143,9 @@ instance DisplayAble a => DisplayAble (Maybe a) where
 instance DisplayAble a => DisplayAble (E.Value a) where
   display = display . E.unValue
 
+instance DisplayAble a => DisplayAble (CI a) where
+  display = display . CI.original
+
 -- The easy way out of UndecidableInstances (TypeFamilies would have been proper, but are much more complicated)
 instance {-# OVERLAPPABLE #-} Show a => DisplayAble a where
   display = pack . show
@@ -144,11 +174,38 @@ trd3 (_,_,z) = z
 
 -- notNull = not . null
 
+mergeAttrs :: [(Text, Text)] -> [(Text, Text)] -> [(Text, Text)]
+mergeAttrs = mergeAttrs' `on` sort
+  where
+    special = [ ("class", \v1 v2 -> v1 <> " " <> v2)
+              ]
+
+    mergeAttrs' (x1@(n1, v1):xs1) (x2@(n2, v2):xs2)
+      | Just merge <- lookup n1 special
+      , n2 == n1
+      = mergeAttrs' ((n1, merge v1 v2) : xs1) xs2
+      | Just _ <- lookup n1 special
+      , n1 < n2
+      = x2 : mergeAttrs' (x1:xs1) xs2
+      | otherwise = x1 : mergeAttrs' xs1 (x2:xs2)
+    mergeAttrs' [] xs2 = xs2
+    mergeAttrs' xs1 [] = xs1
 
 ----------
 -- Maps --
 ----------
 
+infixl 5 !!!
+
+
+(!!!) :: (Ord k, Monoid v) => Map k v -> k -> v
+(!!!) m k = (fromMaybe mempty) $ Map.lookup k m
+
+groupMap :: (Ord k, Ord v) => [(k,v)] -> Map k (Set v)
+groupMap l = Map.fromListWith mappend $ [(k, Set.singleton v) | (k,v) <- l]
+
+partMap :: (Ord k, Monoid v) => [(k,v)] -> Map k v
+partMap = Map.fromListWith mappend
 
 -----------
 -- Maybe --
diff --git a/src/Utils/DateTime.hs b/src/Utils/DateTime.hs
index 23c08df08..cb9135120 100644
--- a/src/Utils/DateTime.hs
+++ b/src/Utils/DateTime.hs
@@ -9,6 +9,7 @@
 module Utils.DateTime
   ( timeLocaleMap
   , TimeLocale(..)
+  , currentYear
   , module Data.Time.Zones
   , module Data.Time.Zones.TH
   ) where
@@ -55,3 +56,9 @@ timeLocaleMap extra@((_, defLocale):_) = do
     localeExp = lift <=< runIO . getLocale . Just
   
   letE [localeMap'] (varE localeMap)
+
+currentYear :: ExpQ
+currentYear = do
+  now <- runIO getCurrentTime
+  let (year, _, _) = toGregorian $ utctDay now
+  [e|year|]
diff --git a/templates/default-layout.lucius b/templates/default-layout.lucius
index 25a12154c..f55073584 100644
--- a/templates/default-layout.lucius
+++ b/templates/default-layout.lucius
@@ -428,10 +428,10 @@ input[type="button"].btn-info:hover,
   display: inline-block;
 }
 
-.list--comma-separated > li {
-
+.list--comma-separated li {
   &::after {
     content: ', ';
+    white-space: pre;
   }
 
   &:last-of-type::after {
diff --git a/templates/table/cell/body.hamlet b/templates/table/cell/body.hamlet
index f2892c2a2..46bf50fd1 100644
--- a/templates/table/cell/body.hamlet
+++ b/templates/table/cell/body.hamlet
@@ -1,3 +1,4 @@
-<td .table__td *{attrs}>
+$newline never
+<td *{mergeAttrs attrs [("class", "table__td")]}>
   <div .table__td-content>
     ^{widget}
diff --git a/templates/table/cell/link.hamlet b/templates/table/cell/link.hamlet
index 21ce1108a..0ced27282 100644
--- a/templates/table/cell/link.hamlet
+++ b/templates/table/cell/link.hamlet
@@ -1,2 +1,3 @@
+$newline never
 <a href=@{route}>
   ^{widget}
diff --git a/templates/table/cell/list.hamlet b/templates/table/cell/list.hamlet
new file mode 100644
index 000000000..86a1f0520
--- /dev/null
+++ b/templates/table/cell/list.hamlet
@@ -0,0 +1,5 @@
+$newline never
+<ul>
+  $forall (attrs, widget) <- cells
+    <li *{attrs}>
+      ^{widget}