So, I went to a previous save, and tried Oasis Landing again. Soon as Autumn had her job, I gave her a customized outfit. She also had invited her future spouse into the household.
As he's improving the meal quality on the replicator, lo and behold...same issues as before started. Everyone went invisible, reset, were not selectable.
I'm going to just disable ITF and play out the last two gens without it, this is aggravating me so much, I'm about to ditch the file. Which would be a shame, because Autumn's child would be the last heir in the entire thing.
Bleh!
Edit: So, the very last save I have pre-Oasis Landing is apparently also glitching, since Autumn was wearing ITF hair and clothes. She's getting the default red-brown hair, and when I take her to a mirror, I can change it, but the game will not accept/cancel the change, nor can I use the menu. I'm afraid the next most recent save that is not afflicted by ITF is when she was born.
If necessary, can I reboot her all the way back to there?