I know this is an old thread, but I have the same situation - Perfectly good Denford Micromill 2000 lacking software, wanting to run it on Mach3.
The above advice is to replace the steppers, or the main board. Why is this? Is the driver board specific to the software?
Angel Tech says I can just replace the control board, which I assume is the largest board, called "Denstep", and wire a new board to the other components. I happen to have a CNC2PC breakout board. It is a C11 Rev 5.
Will this work?