Part of a dungeon level being separated from the rest is a known, but fairly rare, problem with the level generation.
If you can get the summoning doll on the other side of a wall (as in
armory trick in act 1), you can have it drop a teleporter stone on the ground there to get your main characters through.
alternately:
Teleporting anywhere (via hex editor)Check your PM (click 'My Stuff' in the top menu bar, then 'My Messages').
