6666.66*400/60=44.4kHz which implies you've set the kernel frequency (goto Config->Ports and pins->Port Setup and Axis Selection) to 45kHz. Exceptionally few parallel ports will manage that, so start with 25kHz.

There is no need to use the auto-tuning since you know all the parameters - pitch of screw, microstepping setting and pulley raito, if any? Just work it out using the method Sean has suggested:

Step/mm = 200*10/5=400 using 200 step/rev motor, 1/10 microstepping and 5mm pitch screw. At 25kHz kernel frequency you will be limited to 25000/400*60=3750mm/min which is passable but a bit slow, so you could change to 1/4 microstepping as that gives 200*4/5=160 step/mm and 25000/160*60=9375mm/min.