Hi, Edmond
Are you saying it's lousing step's or moving without any command's ?
Is the Z problem both in up and down ?
Have you tried changing Config, Motor Tuning, "Step/Dir Pulse's" from 0 to 5 ?
Are the stepper control's all the same and set the same in Config, Port's & Pins, Motor Output's, "Dir/Step LowActives" ?
If not, Reversing an axis direction should be done in Config, Homeing & Limit's
Hope this Helps, Chip