Is there a forum that talks about downgrading to a previous firmware?
I have a V2 Smart Controller (SC). So this is how I downgraded from the beta FW constellation back to the official FW (app and aircraft):
1) Before downgrading the app you should back up all your files on the SC (flight logs, missions etc.) you want to keep, because downgrading will erase the current individual files and settings!
2) From the SC's Android Apps system settings choose the option to revert the "Explorer" App to the original installation state. (3 dot options menu)
3) Download the official SC "Explorer" App and copy it to a USB stick.
4) Install the official "Explorer" App from the USB stick inserted into the SC. Then keep the SC running with the reverted "Explorer" App (with welcome or camera screen).
5) Download the official aircraft FW and copy it to an mSD card.
6) Install the official aircraft FW from the mSD card inserted into the aircraft and turn it on. On the SC the progress of the aircraft FW downgrade then will be shown.
7) As finally shown on the SC app screen shut down the aircraft, restart the SC and turn back on again the aircraft. You can check the downgraded FW versions in the App settings under "About".
8) If you want to have all your flight batteries on the same (downgraded) FW version: turn off the aircraft, put in the next battery and repeat steps 5) to 7)