For those that are following this, and who come along later: The problem slowly resolved itself over several days. At the time I wrote the original post, I had 4000+ items in my inventory. I now have 10,000+ items in my inventory. Obviously, with that many things, I can't be sure that nothing is missing but the important (to me) things are there and working. No idea why it took that long, maybe the items in long term storage out in the Alpha Centauri system just take a while to make their way back. 🙃
Now I can go looking at the new things and techniques. So far, I'm not convinced about new clothes or hair, but mesh and bento look very interesting.