It's door nr. 3, before the final trial. You can't lockpick it and just before it, there's the vase which contains the bomb.
The "mod" is actually:
killap's Fallout 1.02+ (1.02.27.3) English Patch - (Manual Install)
Sorry for not being more specific.
Thanks for the help! :)
..It doesn't take any damage? It says after the bomb has gone off: The door didn't even take a scratch...
It's the door after all the traps etc.
I just installed the unofficial mod and now this happens and I can't seem to locate this particular problem anywhere else on this forum...