» Wed Oct 12, 2011 3:24 pm
Looking at your video, it looks like you have a room-bound problem. The corridor (or part of it) is only being rendered when you walk into it, which suggests that either (1) you have a rogue room-bound lying around that is maybe left over from previous editing or (2) there are no portals between the corridor and the rest of the cell.
Go to view -> show/hide window and tick the 'portals and rooms' box. This will then show you the room bounds in your cell.