RE: Twist 60 knife edge?
It sounds like you have some control cross coupling. Most of this is design but is also influenced by CG. What most aerobatic airplanes do is when rudder is applied you will also get a pitch change. My guess is that it is pitching towards the landing gear. Moving the CG forward will help that situation. You can employ a mix to fine tune. The roll couple is a dihedral thing. Other then changing the dihedral this can be delt with using a mix as well.
All this is dependant on the fact that the airplane is built strait in the first place. Make sure the wing and stab are level.