Thanks for all your time and help! I really appreciate your efforts. I'll post around on Nraas and even Mod the Sims to see if anyone has a better understanding of what's going on. I need a mad scientist!
I've been using CAW for years, but I've never done anything with the hexes. I've looked at files in s3pe but I don't know what any of it means.
Logically, the orphan object code has to have some sort of origin, but I've reinstalled all mods (updated - and even my sliders seem to work fine with the new patch), saves, savedsims, library... I've gone through every folder of my backup and I can't think of anything that I missed. And the fact that this exact thing happened the last time I installed everything is really concerning. I had a couple of dummy saves from other worlds like Moonlight Falls and Midnight Hollow, where I'd harvested some houses to populate my custom world with Victorian homes.
I have fairly recent backups all of my homes and major families saved to the library, but for some stupid reason I didn't back up most of my commercial lots. I was basically done building the world.
There has to be a solution in the hexes somewhere. Thanks again for all your time!