Thank you for the advice! I haven't been going into my old save with the Gallery lots since I'm worried it could cause problems- when I can get into the game, I test in a new save. Usually, though, I'm just stuck on the title screen forever with the app not responding and I can't play any saves at all. Could deleting my old save with the Gallery lots be helpful, or do I not need to do that?
I've checked for known issues, and I'm planning on testing all my cc soon and checking if the game works without it. I think I might just have too much cc with the new medieval stuff I downloaded? I'm really not sure since the game initially worked fine with the new cc and only stopped working after I downloaded a bunch of Gallery lots and went on Facetime while I played it, and as I've been testing the game will occasionally work with just my medieval build/buy or gameplay folder, but usually it doesn't. There doesn't seem to be any pattern to when it works vs when it doesn't, and now it's not working at all with my old cc, which is an issue I've never had before.