I learn new things about Intel AMT all the time. Yesterday I was trying to figure out why I kept getting "Not Permitted" error when trying to send a "Power Down" remote command. Someone inside Intel hinted that it may have something to do with Serial-over-LAN. After checking, it did! If you have SOL connected, you can't send a "power down" command. The version 0.20 of the "Intel AMT DTK" will have a fix; I will be releasing it inside Intel later today.
I also noticed that the DTK tutorial videos are online. Check them out!