I had the case too.
You enter the BF from outside, and the inner entrance is in a narrow tunnel.
You end next to the inner entrance but outside of the map.
Leaving BF and coming back just give the same result.
Happened for me in Act3 BF3, some templates have probably bigger probabilities to end up in such configuration
What i had in another one, was a room that i could not enter cause a big monster skelton was blocking the entrance of the room. It was the only entrance to this room but fortunatelly it was not the room with the entrance to next level. And you probably can enter the room by using the pyramids.
