Just a teaser
Driving the axis is the "easy" part. You'll need to add a few features to PathPilot for it to be useful. For example a C-Axis DRO and Work Offsets:
A means of jogging is also essential in my opinion. I wrote my own Shuttle component to replace the stock code.
Although Tormach went to the effort to personalize my Shuttle with my name ("Step" ) I decided I could put it to better use.
Perhaps not for the fainthearted.
Step