I'm not sure if I had read the wiring correctluy, but do you plan to run wire from the sub's high level output to your speakers?
If so, you may want to avoid that. Your MMG signals will be contaminated thru the sub's crossover. I'm not familiar with your subwoofer, but try to run the MMG straight from the amp.
You can try both methods and see which one method you prefer though.

But most importantly, congrats and enjoy your new toy. Do you plan to mess with the MMG's crossovers?

Have Fun,
JRA