Thanks for the reply,
Sorry for the lack of info but I didn’t know what you might need.
I’m using the program that came with the machine which is CNC USB, I think it’s part of Planet CNC perhaps not ideal but I am using a laptop with a USB ports only and no D25 printer port.
My x y and z axis are set at 400.000 steps per unit the initial speed is set at 100.00 and the acceleration is set at 15.000
The feed speed is 250.00 and the Traverse is at 500.00
I have checked the movement on all three axis with a digital DTI and the y and z are both repeatedly correct and nice and smooth and quite.
But the z drive is clunky and noisy and not accurate if you set 10.0000 mm you may get 11.89 or 11.08 it’s different on each run.
I hope this is of help.

Many thanks Len.