I presume you are using Cedega? Did you install it with Point2Play or just straight from Cedega? I would go in and completely delete all files associated with your first installation. There may be an old configuration file somewhere that's not compatible with the version you just bought or something.
If installed straight from cedega, look in /home/yourhomedirectory'sname/.transgaming/c_drive/Program\ Files/
If you installed with Cedega, look in your /home/yourhomedirectory'sname/Point2Play/ somewhere...
Then, after deleting all old files, do a fresh re-install with Point2Play.