If it gets too much colder you might need a heating pad on the trans pan... I just gooped a bunch of RTV onto the pad and stuck it on, then went around the edge with more to seal it from moisture getting in... I've got a 125w pad on mine, it keeps the fluid thin enough to get me going without an issue. If I don't plug it in I'll get some slipping at first, in first, but then it goes just fine...
If you can get a tuner, raising line pressure by 5-10% really helps.
Sucks about the motherboard, hopefully the rest of it is still salvageable...
That's the one thing I'm thankful for, up here it's too cold to use salt, it wouldn't do anything regardless. Just small gravel at intersections and plowing the worst spots every so often... The roads are pretty much just sheets of packed ice, and they stay that way until spring.