[cwl1979]

1 yes you should be, unless the electric elements a toast.
2 yes put them on heat and it should be right
3 not that i can think of
4 that sounds like possibly a cube relay issue on the aqua hot itself

Have you checked the switches on the main panel above the microwave to make sure they are in the right position?
One should say something like heat on and A/C off. Another one should say diesel Aqua hot. Have you tried running it on just the diesel side to make sure it works?
For what its worth i just completely rebuilt and rewired mine myself, I'm sure Trainer will chime in, but this piece of equipment isn't that complex, its just a boiler like we have in a house with 3 ways to heat the liquid instead of 1.