http://www.larian.com/forums/ubbthreads.php?ubb=showflat&Number=398413#Post398413

Please install the latest patch from Xbox Live. This will solve any savegame issue you have such as disappearing doors and appearing in incorrect positions. If you cannot update: do not overwrite your savegames as this is the cause of the issue.

Deleting and making new savegames is a possible workaround.

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