Looking for advice? Is my DB25-1205 breakout board faulty?

The motor specification you linked to states 1.8 degrees per step so Motor Steps Per Revolution should be 200.

With 10 microsteps, a 1:1 ratio and a 5mm pitch you should end up with a scale value of 400. (200 x 10 x (1/1) x (1/5))

Cheers, Phill

If you are using stepconf for your above settings you need to enter as in the attached screenshot.
Motor steps is the actual physical motor steps, for your motor it is 200.
Driver Microstepping is the number of microsteps per motor step, for your setup it is 10.
Some drivers confuse the issue by saying 2000, when they actually mean 2000 total steps per rev. (200 x 10).
If you enter this confusing value in stepconf for the motor revs then you need to enter 1 for the microsteps as this is the total number of steps required per rev.
If you look at the bottom of the screenshot the Axis Scale is 400, this is what is transferred into your ini file as Scale. This is the important value and it also shows how it is calculated using the top four rows of the screenshot, the 0.2 being 1mm/5mm because we are calculating the number of steps required to move 1mm.

Cheers, Phill.