#1: Yes. And since the outputs wont turn on until windows is loaded, 100% anti-thump proof.
#2: That would be easiest achieved through the "speedvol" settings in RoadRunner. Uses GPS. With the brain, it can be done for sure, but you would need a speed sensor such as on your wheels. So you can do it 2 ways.
#4: Again, you would need a speed sensor. But yes very doable.
#5: Are you sure it is 1-wire frequency, or is it 1-wire resistive? Either can be done, but require completely different methods to hook it up.