As long as it uses a bipolar (4 wire) stepper motor to drive it's motion, it can be done. Not that I've used it for anything other than just playing around but I built my own from a dividing head off ebay. Things to watch out for:
1. Rotation direction. If your spin direction is reversed from expected, either check that you have the correct axis orientation set up in CAM (X+ means the work points to the right, 4th axis is on the left of the table) OR reverse the two wires on ONE of the steppers poles (if you flip both poles, the rotation will not change)
2. Axis scaling. If you command 360° but the axis moves something other than 360 your scaling is off. First thing is to check your stepper drive dip switches to make sure they are set correctly. If that doesn't solve it, you can change the scale factor for that axis in pathpilot but you will have to do this every time you update pathpilot to a new version. For reference, the standard 6 and 8" 4th axis from tormach is a 90:1 ratio while the microarc is something else (can't remember off hand). My dividing head was a 40:1 i think so I had to change the scale in pathpilot to make it work properly.