That was installed far after.
Sorry for the late replies, it has been bedlam here and I have been unwell.
I have tried so many things since the post. A fresh reinstall of windows… A fresh install of retroarch in default folder, a fresh install of the manual retroarch into the documents folder which would have absolutely no write permission issue (but if it was that in any case, other cores wouldn’t rewind).
Ps1 rewind is no issue either (beetle PSX HW).
I even installed just retroarch and downloaded kronos core, installed saturn bios into system folder, NO other cores or bios, nothing else at all, and it crashes as per always.
Playing games in kronos works fine.
Absolutely no standalone kronos or yaba sanshiro on this fresh windows install.
heck, I can even rewind in flycast, no jokes. It’s slow but it works.
The problem is that rewind works via save states, and save states just won’t work for me with kronos…not that I’d ever want to rewind in it, if I really wanted to do that I could use Beetle Saturn, but the point is that save states themselves crash 100% of the time.
I even didn’t install bitdefender this time and am using default defender only, in case it was that!
I don’t know what else to try.