1. The way I do it is by filling a container up with hot (not scalding, but hot) water and then putting the rodent in the container and leaving it until it is thawed. This process takes less time and is easier IMO.

2. When my snakes are in shed, I mist them once a day and have had nothing but perfect sheds. But I use rubbermaids as cages so they hold humidty well anyway. You may need to do some extra work if you're using a glass tank.