I don't know. But I do know that you'll have a tough time at scanning your own ports, from the same location, in a meaningful way. What matters are outside scans from a remote terminal going into your home computer network. There are windows programs for opening ports and scanning ports, or you can write mIRC scripts that will do this too with /socklisten and /sockopen. This way you can get positive feedback on whether you can access a port consistently from the same remote location over multiple attempts over time. But you'll still need access to a computer away from home to conduct the scans.
When you have DCC ports reduced to a single port, only one transfer can take place at a time.
