Re: Uninstall and reinstall

1. I would install the base game and then patch it to the newest patch. After that, check if the game works as intended without putting any of the EP/SP or user data back. If you're satisfied, install the EPs in the order of their release. For some, you wiill get a message that your game is newer then the EP you want to install. You can safetly ignore that message.

2. I would first start playing a new savegame without putting any of your old data back. Check if your problems are gone and if it's fine, you can start putting the stuff back.