Debugging on server showed that Mover1.RotationRate is (0,0,61440) instead of map's value of (0,0,-4096). Remarkable is that 61440=0xF000 and -4096=-FFFFF000, and on Wiki I've read that rotator components are compressed to the size of a byte - so the Roll value seems to be clamped in a way.
Any hints to resolve this?
Sometimes phrasing the question includes the answer... I just passed the problem by with turning the wing wheel 180° around its z-axe and changing the Roll from -4096 to +4096. That value is replicated fine.