I've done my research, and read a lot... but I have a few basic questions.
First, I was not able to get any DC equipment to turn on in the vehicle, so I assumed the Coach Battery was disconnected. I found this guillotine connector under the hood on the passenger side, and closed it [see below for a picture]. Now the equipment turns on, but very dimly. Does the Coach battery charge if this connector is open? I assume it needs to be closed to charge the battery during charging... but do most people disconnect the battery when they are away from the camper? Is there a better disconnect people have used? Should I consider repositioning the circuit to an interior switch to more easily engage/open the Coach battery circuit?

Secondly, what is the red illuminating switch below the tank monitor? I think it is the water-heater, correct?
Third, What are the items on the battery/tank monitor panel? Holding Tank #1 is that usually Grey? Is Holding Tank #2 usually the Black? The BAT COND indicator measuring the Coach battery, not the chassis battery, correct?

Fourth, For the upper cabinet switches... what is the small black switch above the 12-volt outlet and beside the cable TV coax plug? I know the white house-light switch is UP to power the cieling AirCon and DOWN to power the microwave outlet.
Fifth, What is the hole in the middle of the wall for? Was there a monitor panel there that was maybe removed when the unit's generator was removed? It looks like a factory drilled hole, but what went there?

