This last cut was successful, so what I’ll do next is run the project with the BitSetter, measuring each step.
I’ll use a probe (rather than a bit) and the stock to set the zeros, remove the stock, and ‘run’ the project with the spindle off, then ‘rinse and repeat’ with a manual zero.
The issue is only with the Z zeroes, not the X and Y.
I’ll let you know how it goes!