Well I finally got the pro built - lots of redo with limited instructions. I turn on the Kossel Pro and the extrude head comes down and touches the plate in several places. Then it moves off the plate and trips the touch guide and freezes - on the matter android phone app it says the extruder heat is 650 degrees to 8oo degrees - but is cold. The glass plate is cold. We hit the Y+ Y- buttons on the app and nothing happens - my son hears a whine coming from the machine. We hit the release button and the whine stops but still no movement on the extrude head. We have double checked wires and even putting in several c codes we cannot get the extrude head to come down. We click on the home button - it rises to the top - does a little jig as it touches each button and then stops. Any suggestions?