The coefficent CL_dr was too high so the Roll Moment with Rudder was not compensated by the other Roll Moments.
That has been fixed in FSX in setting CL_dr to ZERO.
Therefore it was even possible to decrease CL_beta (Roll Moment - Sideslip (Dihefral Effect) . I have not tested this effect.
A test shows: The plane does not roll anymore against rudder deflection.
I have not studied the effect of reduced dihedral effect.
