While this isn't as technical as the other problems here, this is an in-game problem that seems not to have an in-game solution, including any uses of the Exile Editor I can see.
My party used the Orb of Thralni to fly over a river to a small ledge, just east of the Crypt of Drath. However, there's a group of monsters in the narrow tunnel back to "land," and you can't fly over monsters. There are two other ledges I can get to, one north and one south, however neither allows me any option of flying elsewhere.
Screenshot available upon request.
Is there any known solution?