Re: "The game failed to save. Error code: 526"

I've got a couple of back-up saves lying around, I think the oldest one is the broken save.

But I've managed to find a sort-of-workaround by uploading the sims in my broken save to the community along with any lots they lived in, starting a new save, then placing them back into the world where they were before. Though I did lose all the achievements I had not tied to specific sims stats and any relationships any sims had built up...