Hi, Archerks
Change the Step & Dir. Low-Actives to Opposite State in Ports & Pins, Motor Outputs, The Steps Per should be 2000 X Turns per inch on your Ball Screw.
Start at a vel of 20 or so and Accel. of 5 and work your way up from there,
Make sure you have the Gecko's on a Good Heat Sink's / Fan cooled, You Should be able to turn the Limit up all the way up as your servo's are rated at 8.8 Amp's Cont.
Gain & Dampening can be tricky, Adjust the gain up till the motor start's to vibrate then adjust the Dampening up till it stops, Repeat this and run the servo's some, The Gain set's the Power/Torque of the servo.
It's All a Balancing Act, Take it Slow. If you feel the geckos or motor's are getting to Hot, Turn the Gain down some.
Hope this Helps, Chip