I cant help there Im afraid. I have no experience with the physics.
MAYBE, physics causes different 'frames' to have severely different durations,
so try this addendum to the end of my code and see if it smooths things out.
Code:
...
vec_set(Rot_Speed, vector(ang(Rot_Speed.x),ang(Rot_Speed.y),ang(Rot_Speed.z)));  // (optional) CORRECT odd looking angles to -180 to +180 range
vec_scale(Rot_Speed, time_step); //or vec_scale(Rot_Speed, (1/time_step));

Any Physics gurus listening in on this issue?

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