Welcome, and congrats on your new rig!
I feel for you, having to live in that cold. I'm in So. California and a cold day for us is anything in the low 60s-high 50s.
As far as staying cozy in your rig, I think your biggest challenge will be condensation. And I have absolutely no idea how to combat it while living there. Hopefully someone with experience in cold climates will chime in and offer some suggestions.
Enjoy the adventure! By the time the snow melts you guys will be pros at living in your motorhome.