For all who want level on glass

[Artezio]

@DrBunsenHoneydew yes, by connecting directly to the machine.

Finer adjustments to z offset?

At a USB console (Luban or Octoprint) type G1029 D -x.xx where -x.xx is how far you want the nozzle to go down. Negative down, positive up. Remains until you next calibrate. You can adjust as much as you like but has to be under 1mm at a time!