https://dl-web.dropbox.com/get/Photos/Elemental_1285090240.jpg?w=640d6789
After I lowered the land the terrain remained at its original height. Thought maybe it would fall back down to earth after a few turns, but it did not. Might be a bit hard to see, but the trees, and some of the parts of the city are floating.
Everything else is very stable for me finally. This is the first time I have made it this far into a game with no crashes! Starting to appreciate the city building aspect of this game.