I am pretty sure it was a Steam problem (their crack support team has not replied to my email). It wasn't a crash, the game just wouldn't start
I re-opted for the patch and it works fine now so I can't see it being a GCIII bug. Heck it might even be on me. I might have made a bad mouse click or some such.
If you still want me to submit a ticket I will, but since no one else has had a similar problem and I can't duplicate the problem, it would probably not be worth y'all's time.