Hi, Pablo
I think the sherline 1\2 step mode is the widest pules width Mach has.
Some stepper controls are sensitive to leading and trailing Edge Pulses (Dir, Step pulses, X'ed or Checked).
Try them both ways, Ether "All" Checked or X, "Your Axis Directions will Reverse", So be Care-Full (Test center of Table).
Direction change should be set in Home & Limits page (Reversed Coll-um).
Hope this Helps, Chip