Bug in Z height calculation when printing a Vase

Cetus mk2 or up studio has a math bug.

This has been a painful one to track down.
I have seen odd slicing artifacts for a while which has always made me wonder but now I am certain it is a bug.

Stepper motors are inherently delta devices, a number of steps clockwise or counter clockwise to get to the next position. The problem is that the Tiertime software tool chain someplace internally calculates the stepper motor delta but then discards the rounding errors!!!

This is easy to verify with gcode generated by the latest Prusa slicer. How to configure and generate gcode for Cetus.

In Vase mode (single wall with continuously incrementing Z) slice a round object and also a cube object and then print both. The round print fails because the Z height incremental change is small and is mathematically rounded to zero in every Z calculation so the height never changes.