I found a workaround for this problem, since the animation blueprint does not work like I want:
I baked the animations/controllrig from the sequencer to a new animation and used that as input node for the animbp.
In a new level sequence, I add the animbp to the character, and it plays the animation, together with the spring/rigid nodes. Although, the position of the character was off…
Adding additional animations will break this. So, I have a “workfile level sequence” and a “renderfile level sequence”, for the same scene.
**It may also work with an animation montage, but i did not look into that. **
Regarding the crashes: Now that I removed the animation blueprint from the SKM / BP, it rarely crashes.