Quote from Capt0z
Finally got round to reinstalling this. It's great! (Not that I expected anything else). I loaded up my old world, but I'm in a completely different world (as far as I can tell). A pity, because I had built a themed house out of each of the dungeon blocks. But thankfully, I kept my inventory. That amount of artifacts/rare items would have been damn hard to recover.
So now, off to building a new house and taming some more Moas.
Load a new world(or use your old one, just delete the Aether folder), preferably with the same seed, then visit the Aether so that its folder is generated in your save file, then, in your old save file, find the folder that contains the Aether saved files!(for Example the Nether is named DIM-1! I don't know how the Aether is named!)
Copy the file(s) that you think they might contain your structures!(or just copy all of them, rofl)
I don't know if this will work and I don't know what other possible consequences it might have in your world!
Remember to keep back ups!