I have a P2 Zenmuse GoPro. I modified the transmitter with a potentiometer to control gimbal tilt that worked great, much better then the factory lever on the back of the transmitter. After doing the latest firmware update that relates to the "new" controller with the tilt wheel, my potentiometer will no longer calibrate with the DJI assistant. I select the radio button for the legacy controller, not the new one, but my gimbal only moves full up or full down now, It no longer calibrates correctly after multiple attempts to calibrate via the P2 Assistant, versions 3.6 and 3.2. I knew the risk I was taking by modifying the transmitter, but is there any way I can downgrade the firmware, to restore gimbal pitch control, or has my transmitter just lost it's gimbal tilt feature permanently, turning it onto a lump of spare parts?