Qidi Technology X-One 2

I have a 2 head machine and the heads are not the same height.  The documentation does not include any information about how to make the adjustment.  In the end you start just using one head.  You have to recalibrate the print head clearance each time you want to use a second color.  I also had trouble with the filament feed servo motor set up.  I am in the process of modifying the unit to have extruders with a different design.