You could try running trem thru cmd.exe. I think it's something like: Start->Run->cmd.exe, enter->cd "C:\Program Files\Tremulous\"->tremulous.exe (and whatever +sets are in the properties of the shortcut you use to run trem if any), but I'm not sure, so if some windows user comes, correct me if I'm wrong. That should log all the console text in cmd.exe and you should see any errors there.