Well, thanks everybody!
I've decided to start my neighborhood over again. Hopefully knowing not to switch out folders too often will hold off corruption better. Thankfully, I hadn't done much playing, just setting up. It'll go faster this time, because I took notes and I took some screencaps of the old 'hood to work from. Again, thanks to all!
Hey- if you said something to me in a post and I didn't write back, I'm sorry. Sometimes I don't feel good enough to post and by the time I'm able to the thread's old enough that I feel kind of weird about bumping it just to post one or two sentences. So please don't take it personally! :)