Chinese Stepper Driver - ZK-SMC02

I'm having trouble getting this stepper controller/driver to work predictably. It works, but the actions are not making sense. I can set registers and push buttons to get the motor to step. However, small changes in registers have large changes in step size. The full-step, half-step, quarter-step etc dip switches do what I expected, but not the registers.

I'm pretty good with electronics and steppers, but not so good with software. This unit is for sale at https://www.amazon.com/dp/B0BFRTCVPR The front panel says ZK-SMC02. I'm only running it from the front panel, not from the interface. I've attached a photo of the front panel and also the manual so you can see what this is.

My goal is to use this to turn a 1.8 degree stepper a specific number of steps every time I press the advance button so I can cut gears.

I guess it's possible that I got a defective unit, but it does seem to index somewhat, so it isn't completely bogus.

Is anyone here familiar with this unit or anything similar that can help me either here or off-line?

Thank you.

Have you tried setting F01 to P04. F06 should be set to 1, and F02 set to the number of steps to move.

p.s. How do you measure the amps when changing the potentiometer on the bottom?