I did have issues with the gear doors. I was so disappointed that I set aside the Mustang for several months. I am now working on installing micro servos and using a sequencer to operate the gear doors. I just could not get the mechanical gear door system to work on this model. Using micro servos and a sequencer seems to have some real possibility and so far, looks as though it will work. I will post pictures and other info as the work progresses.
Best wishes and good safe flying.
Heli-NuBee (AKA Roger the radial rabbit)