It all connects, but the print will not start

Vertex 3D Printer Vertex - Printer software (repetier, slicer, ...)
1

Hi, this is my setup: K8-200, Z-axis upgrade, E3D-v6 extruder, Windows 10, Arduino 1.68, Repetier Host V1.5.4

I can connect to the K8-200 with Arduino and upload firmware, no errors.

Can connect to K8-200 with the Repetier Host. I have full manual control of the printer. Can load an *.stl, with Slic3r or Cura.

The ‘Start Print’ gets things started, bed heats, extruder heats, all axis’s go to the prep position.

Then I stare at it for, well it doesn’t matter. The actual print job will not start. Except a random one time only print start by rebooting the laptop, resettting the firmware, disconnecting and reconnecting the power to the printer (still can’t replicate the actual combination of these steps to get it to print one time).

Help! Any help! What the heck am I doing wrong?

Thanks for all suggestions or other’s similar experiences.

Regards,

Dan