Can you see in the game data map tile sets?
I'm curious about some potentially missing areas.
If you recall the gameplay release trailer from 2008, it opens up with a section that has a shallow pool of water which all the ghouls climb up to. Then at the end of the map, there is a room with 2 curved stairs heading up northwest. Pretty much every other section in this trailer made it into the game (most, if not all is Cathedral tile sets), but those sections are not.
Not to mention that there are those spots that look like they could have a dungeon but don't (end of Stonefort, mid section between Halls of Agony 2 & Prison bit).
In Act II at the mines area there is a door, was on the east up a short flight of stairs, that looks like it leads to some mines. If you walk up to it and stand practically inside the door you'll leave and can re enter the "mines" area that you WP'd to.