You can transfer it. Just make sure you have the key in a safe place that you can copy and paste it. I emailed mine to my gmail account because I do not have a email program on my burning PC. I ordered with the PC that I check almost daily and it has an email program. I then downloaded and installed on the PC that I wanted to use it own. I have also reformatted HD before and reinstalled.
As for discount on 2nd license, I think Signals purchased one for his son so maybe he can tell you. Or email Fengtao.