Lego Technic remote controlled cherry picker 8292 + 3 motors

I've added 3 extra motors to do a few extra things like drive, steer and the third changes the function of the original motor. Originally hand operated switch changed gears, allowing the original motor to perform 2 different functions (raising and lowering the platform and turning it). The chain connecting the forwards and backwards movement isn't coping with the weight too well, so you can hear a clicking sound when I move it forwards or back. I did the best I could. The doors are permanently open so the recievers fit inside. I used the motors from the bulldozer set 8275.