question

The problem is the "prop_mod_moment_scalar_yaw"
this is a straight multiplier on the whole aircraft and not the propeller itself.

So, to summarise my rants.

The "prop_mod_moment_scalar_yaw" seems to not multiply the effect the prop has, but the effect the engine position (and prop) has on the whole filight model. So instead of the center of pressure moving 10, 20, 30cm to the right, it feels like the engine's position (4,5,6 feet) is multiplied.

Anything above a value of "0" breaks the taxiing, no idea why. if its only a 1x multiplier it should behave normal, but it doesnt. Switching to the legecy prop model works again.
https://www.youtube.com/watch?v=219PhpWDM1Q

Setting a value of "0" works normally on the ground, but then obviously removes all P-Factor of the engines

https://i.gyazo.com/c3a5ba528d6a3ccfbe75a618079dcd76.mp4

To get accurate P factor during climb and cruise i had to use a multiplier of 10x. With both engines running is perfectly fine, but going asymetric breaks everything. The effect is over the top and the plane can now breakdance.
https://i.gyazo.com/9876781d725f5c5af1cf7da7dad59e4e.mp4