I downloaded Dead Money off Xbox Live, and have two things happen:

-Sometimes when I go to the location Northern Passage, it is blocked by boulders, and then sometimes it isn't. It goes away when I fast travel and come back.
-If it isn't blocked with boulders, I enter it, go to the end of the tunnel on Dead Money side, and the text "Exit to Mojave Wasteland" appears, but I can't go through.

I cannot play the DLC.

Anyone else?

The Northern Passage has nothing to do with Dead Money.

No game-breakers here. The only bug I've gotten from Dead Money is ED-E turning hostile but I've figured out how to fix the problem.

I have one, I'm talking to Elijah and I say to him that's all I need to know he talks for a bit and then the game freezes making me have to restart my xbox, any help?

It's been known to freeze at the start when you have certain items in your inventory. Try dropping everything to see if it fixes the issue.