About the DLC error corrupting save files, mine got really weird. I got it first after leaving my room in novac and the game just froze. When i would try to load any of my last 2-3 saved files, it would go to the loading screen and then give me the error message that the game relies on downloadable content that is no longer available, etc. I've been trying to work around it by using one of my recent good save files and saving often while hoping that the files don't get corrupted. Now however, whenever I get into the start menu, after "loading downloadable content...", i get the message "some of your downloadable content is corrupt and could not be loaded". When i try to load a save game, the error message comes up before loading the game and if I select to continue loading, my xbox just freezes up. All of my files have now become corrupted, even the ones before I started getting the DLC error. The only save I have that still works is basically the very beginning of the game. Am I totally screwed.... :cryvaultboy:

I'm having the exact same problem ... got a save file at 7 hours, an auto save a few mins before and another save file at 2 hours ... all of which i cannot load becase my dlc appears to no longer be availible :cryvaultboy: annoyingly there is no option to redownload the caravan pack i have ... will be really annoyed if i lose my save file. unfortuanately i have not found a soloution to this either

Yeah this is pretty frustrating...At this point I am just interested in knowing whether these files are permanently done for, or whether it would be possible for a future patch to make them playable again.

They are working on it.