1. One should be able to do it in the FS2004 "Settings" - "Assignments" - "Joystick Axes", but I've tried several times, it doesn't work (at least not for me).
You can assign it to one of the many (POV) HAT switches though.
2. Never tried it, but it would be really cool, and I think it's possible. But I've had my current settings for about 8 months now, so I can't change my settings without getting really confused the first couple of times I use them. ;D
3. I've had loads of problems with the rotary control. I tried to use it for the mixture, then the rudder (got that one working, really nice for taxiing the heavies.

). If you want to use it for rudder trim, do this; Open the SST programmer, then select Rotary1 or -2. Press the little arrow button and select "Bands" instead of "Axis".
Then set the band at 50%, and assign 0-50% to rudder trim left, and 50-100% to rudder trim right.
(I don't know whether 0-50% is left, and 50-100% is right, or if it's the other way around)
NOTE- I haven't tried number 3 myself as I'm happy with my current rudder trim setting, but it should work, as this is how you program bands.
I hope this helps!
