Hi, Joe
In Config, Spindle Pulleys, Set a min speed value to start with, You may/will need to also set steps per value and vel, Accl values also in motor tuning.
I don't have spindle feed back hear, So not sure of correct procedure but it's a start.
Directions sound correct also, X- moves in deeper cut, Z- moves right to left tords head/chuck.
Chip