I have the Steam version of the game. I have created a thread on the Steam forums but I'm hoping somebody here could help me as well. When I tried running the game today, I get a message saying:

Performing first time setup...
Installing (step of)

Then it just hangs at this stage forever. I've tried verifying game cache, restarting Steam...nothing seems to work. Am I going to have to reinstall this 9.8 gig game?