I'm also getting crashes during gameplay, I tried bypassing LIVE the same way Fallout 3 works by renaming the cat file to *.bak but the game does not load
I tried the same thing, with same result as you.
Yah I do hope a work around becomes available soon, this game looks good, but im not sure how saving the game will work, cause apparently you need to be logged in to LIVE to save any progress
so meh i dunno
It autosaves quite often.