SU-39's Radar bug

The Kopyo radar now turns the rudder crazy whenever it is installed… I tested it with and without additional load outs and the result is the same.
The rudder is absolutely not stable for mysterious KOPYO reasons… I’m not aware of any directional stability problems for the Su-25T or Su39 when having underbelly addons.

Good job ruining another icon as if the BVR battle rating didn’t kill them both already.
How to report this and where to go?! The aircraft is unflyable in SIM and even wobbles in reasltic mode when having the radar installed.