I have decided to try Sim CNC on my mill but sadly failed at the first hurdle which was when you open the software my IPA controller doesn't show up. Very disappointed as I even did my homework by reading the Sim CNC quick start guide last night. I have just messaged CSL and when I get this sorted I will come back with any updates.
I am quite happy with the look of Sim CNC and as Mach 4 has some issues I thought why not give it a go.