For the flap Mix I can Mix an accessory input to Output 2 (left aileron) and Output 5 (right aileron), but the down deflection is likely to be limited by the previously defined "cropped" throw.
I need flaperon so will try it without differential mix : with a bit of luck, the gyro on the yaw axis will somehow compensate the differential aileron loading. At least the fuse will keep straight (?). Playing with the servo horn could also help a bit. I am not going to roll this glider so the yaw gyro will not have so much work.
Another dumb question: do I absolutely need to define a dummy throttle input, or can I make it do without any input? Is the flight controller going to handle this?