I have a game where I'm running a number of Twallan's mods: master controller, story progression (with the extra and expanded modules), overwatch, error trap, and debug enabler. I'm just playing one immortal sim on it, on normal lifespan where I keep her going through ambrosia. It's currently on week 15. Many weeks earlier I started getting these "Instantiation reset" messages. At first I thought it was just recovering missing sims, but then I realized they weren't really being recovered. Some of these were sims stuck in limbo not aging, not appearing in game, that couldn't be reset. One was Geoffrey Landgraab, for instance, I had normal aging on, but he was still alive in week 8 but unable to appear or be selected. I eventually used master controller to force kill him. It was also happening with some other sims.
One in particular caused a lot of problems. This sim was an adult female who became pregnant and then vanished. I didn't pay much attention to it, and figured maybe I misremembered the pregnancy message when no baby ever appeared. I decided I would just force kill her when she became the right age to pass on, since she had a husband and I was still getting the story progression popups about her and her husband. Well, eventually her husband reached the end of his life. He and her were the same age, but she still looked adult in the Nraas selector, even though her age was like 92 days. I got the reaper message for him, but it kept saying he was getting spared because of the birth of his baby. That happened a few times in a row. Eventually I force killed the apparently-still-pregnant wife so he could die like he was supposed to.
I hoped that was just a random bug, but sim-weeks later I have several more sims that can't be fixed with the instantiation reset, even though "recover missing sims" says they are recovered, and one was pregnant. I used master controller to end the pregnancy and kill her and her husband off when I saw it was the same thing over again; he couldn't die because she was due to have a baby, even though she'd been missing for weeks.
Anyway, my question is what am I doing wrong that this keeps happening? Is my town bugged? Should I try a fresh file? Or is there something I can do to avoid these issues?
Oh! I almost forgot to add this, but maybe it's related. I also get a "graduation callback message" in error trap every sim week on Friday, Saturday, and Sunday. It doesn't seem to cause any other problems, but I don't know if it's related to that. Not to mention my reaper is stuck in graduation robes, because he graduated early on in this game for some reason. I have no idea what happened there. I saw him on the map tags at city hall and thought someone was dying, and to my shock I found him graduating with Bebe Hart and Holly Alto. I reset him when he stayed at town hall until midnight that night. He looks silly, but he's doing his job, so I didn't worry much about it, but thought I'd mention it in case.