They acknowledged there is an issue w/ the 6.3.0_12 image regarding the TS license. They told me to add this to my WNOS.ini:
clearlicense=yes
Think you need to be careful with this because if you leave it in there, the terminal will ask for a new RDP/TS license every reboot–thus leaving you with a bunch of licenses tied up for the 90 days it takes M$ to release them.
This works for me, I just reboot the terminal with that line in, then take it out right after I see the Windows logon screen.