Those codes make it look like you have a EV100 LX system. If so, -06 means the accelerator was pressed with no direction selected.

-074 SYMPTOM
Forward or reverse contactor opens and closes, then opens and can only close by opening and closing the key switch.
POSSIBLE CAUSE
Defective RB contactor.
? Check RB contactor for smoothness of operation
and excessive wear on moving parts.
Intermittent PA6 input.
? Check for loose connections in PA6 circuit from
PA6 to RB contactor A2 connection.
Defective RB contactor coil circuit.
? Check RB contactor coil for proper ohmic value. It
should be 10-14 ohms.
? Check coil connection from PB2 to RB coil (-) for loose connections.
? Check coil connections from battery positive to RB coil (+) for loose connections.

You can get EV100LX documentation from the Flight Systems website.

I'd tackle the -06 problem first. If your directional control circuits are unreliable that could affect the regen braking as well.