Pah co chu puk

I'm converting a JJRC 6x6 into a US Army truck. I tossed the stock electronics and added servo steering and a 40 amp ESC, plus an electric winch. It did great off road for a while, I even had it pulling a trailer, but then the motor seized up. It will not rotate at all. I bought a new truck and switched all the upgrades over to it, so now the original truck is a parts doner. I have a 6 channel controller for it and have the winch on channel 5. The tires, wheels, front winch mount bumper, and rear bumper and pintle hitch, and the trailer, are all 3d printed. Everything works as planned, but I have some questions...

Will the 40 amp ESC fry the new trucks motor?
Is there a limit to how many amps I can put through the motor?
What is channel 3 for? I plan to hook the headlights to channel 3 and I would like to have them switchable from the controller.
What does channel 4 do? It has a three position switch. What can I do with that channel?

Some pix of the truck.

Pah co chu puk

Got it working well. Upgraded the motor and drive train. Drives off road like you would expect an Army 6x6 to drive. The winch works nicely too.