I can confirm that the problems with some old saves. In my case it seems like the newest from the previous version did not work but those, which are a little bit older, worked. So I loaded an older save and skipped fast through the already played parts. And when I loaded from within the game and not from the game menu, also some of the saves that did not work from the game menu then worked. There was an error message, but after ignoring it, I had loaded the save I wanted to load. It seems it makes in some cases a difference wether the game itself is already running or just the game menu has been loaded so far. No idea why, but that's my impression.