I'm having trouble with operating my CNC mill using the Shop_Floor_Tablet UI and the TinyWeb UI.
The following are specifics about my installation:

CNCjs: 1.9.12
Node.js: 8.7.0
NPM: 5.4.2
I installed it via NPM. I am using an xPRO v3 controller, but that is irrelevant at this point since I cannot get cncjs to run on the pi. My pi is a brand new Raspberry Pi 3 model B running Raspbian (i.e Debian) Stretch (I think Stretch is version 9).

When setting the work zero position using either UI, I cannot zero the Z coordinate. Also, the Z coordinate display does not change when I jog the Z axis on my machine. However, when I jog the Y axis, not only do the Y coordinates change in the display, but the Z coordinates change.

Without being able to see my Z axis position, I cannot establish the work zero position. I'm having the problem with both the Shop_Floor_Tablet UI and the TinyWeb UI.