Always making unique saves, I have not run into any door or reloading problems in the NA XBox version. I haven't gotten around to getting my Xbox online for the patch yet (need to pick up an adapter to get an ethernet cable long enough to reach). An update for other regions is going through Microsoft's patch procedure.
Larian is looking into this problem, and assuming the savegame patch doesn't help (at least with the PC version the missing door problem can be caused by quicksaving and quickloading repeatedly), then I would expect a fix in a subsequent patch.
