My two cents worth.
Is it Crayford style or rack and pinion? I found that the most reliable was rack and pinion with a sizeable backlash programmed in.
I have a 3 inch Feathertouch R&P with a SharpSky focuser and controller.
Only time it plays up is when the seeing is too bad to be imaging anyway and it wont get good v curves.
Oh, and set your backlash to be double of what you have and set it to the "In" direction.
