It will go into protect with a 4 ohm load. (breaker will pop) But should do about 3600W before that happens.
Disclaimer: I am not responsible if you shock the shit out of your self.
I got in touch with him and everything is in the process of being fixed. I am texting Mike privately the issue and hopefully this can be locked in a few days.
The Amp Dyno doesn't care one way or the other. It will measure the true power coming into it regardless where it is coming from. You could connect it to a wall socket if you wanted to dyno your house.
Tell me more, I will do it!