gibbeynator: OK, the problem seems to be that I can't just update from 1.1 to 2, I have to install all the patches in sequential order. So, I had the updater for 1.2 downloaded, so I installed that, but now I can't make the jump from 1.2 to 1.35, then the jump from 1.35 to 2.
I was having the same problem after trying to reinstall in order to get rid of the 2.1 patch. Do you have the GOG version, Steam version, or a retail copy?
Because if you have the GOG version what I did was re-download the game My Account. Because as patches come out, they also update the actual game files that you download from this site, so that people who bought the game today can already play version 2.0 right off the bat without having to deal with patches.
So when I re-downloaded the game, it was already at 2.0 with no patches. Now all I have to do is remember to hit the No button everytime it asks me if I want to update to 2.1 since that patch stopped my game from working and is the reason I had to re-install my game in the first place.