Some of my notes. I think this is the degree of what I can assist with without being kicked out of the forum. I reckon that C3D support is careful not to give too much advice regarding warranty liability… “Y2” is interconnected in the X, Y, Z connectors, but else unused? “LIMIT_?” signals goes directly to CPU. BitZero and BitSetter has the exact same signals.
A tip for an emergency stop if the grounding clip from the BitZero has fallen off during probing - press BitSetter 
