Remember:
MAKE A BACKUP.
Then:
Basically you are aiming to restore the game to its pristine state. So:
Change back the GraphicsRules.sgr in C:\Program Files (x86)\Electronic Arts\The Sims 3 Late Night\Game\Bin if you have changed it to get more Sims at nightclubs, and if you have made any other changes to the config of the game files (the ones on your C drive - you have already removed everything in your User files by moving the files from My Documents).
Undo any other changes you have made to the core game files.
Make an alternative New Clean Game