Y'know, I think I found a solution to my problem. I would nominate the Western Settlement (note that the underground quarries in it extend almost all the way to the spire to the north, so may as well include that) as my 'thing to move' instead of my Doom Fort on the condition that a copy of the level files be made available to us. That is, if I have a save file with all my old stuff somewhere, I would be much more willing to give up most of it.

3SC, perhaps we should still dismantle sub-Project POWAH and store the bits in the western settlement so that we can rebuild something similar when we begin the new map. No?