Thank you, Dr. Sassi.
I had no time to investigate since there was a deadline to pre-render the scene, so I used C4D 2024 to render it as it was.
The rig was made 2-3 years ago by another person, so I had no idea how to fix it.
Anyway, I got the answers from the devs on how to fix it:
"We fixed that the "Rest Hold" does not work in <=2025.1.
It just does nothing and was always like 0.0.
With that fixed the rest hold actually holds and 0.5 is a lot.
Lowing that to 0.0 will give the old result that you previoulsy got with it being broken."




