Hi Andy,
You would be much better with a Mach3 conversion.
I had the exact same problem a few month ago. I bought a VMC 260 and it came without any sofware... And Boxford won't sell you software unless you are in the education business...
Any way, I found Mach3 much more friendly and it runs of a modern Windows PC.

VMC 260 and the 300 are cousins really... So If you need / want help on conversion let me know. Too bad you are so far from me, I could have come to your place to help...

Ta,
Laurent