Oh jesus...
You think Steam or Live are bad.
Wait until iTunes gets ahold of your games.
You will never play them on another device in your life, and...
You know what? Screw it...
@OP
Check your HDD, look for the patch. Compare that patch to your saves.
If it isn't there, or is a prior version somehow... download the most recent update. Problem fixed as soon as you get back to your house.
Then, try it again, and post results in the XBOX issues forum. Good luck.
