This did it! You are the MAN!!! I have been trying every possible fix with no luck. My only question is why did this work?
It looks like Steam Cloud is doing something wierd to the save game files, backing them up and then corrupting them. As for why this fixes the launch bug? I dunno. It must be some kind of network gaffe with the way NV connects to Steam, but beyond that, I really do not have a clue.