I'm having some trouble- perhaps I'm doing something wrong? I'm trying to control a camera gimbal I made with RC channels 6 and 7 out, using a USB joystick.  I'm having some trouble with the joystick configuration. I got one axis to work by mapping the joystick X axis to channel 6, then changing RC_6_Function to 1.  That servo moves fine.  After that, the software won't let me map any more joysti…