Hi Col,
Welcome to the forum.
Given that it's not free software, will it EVER get fixed?
There is no further development of Mach3
( also - There are a number of functions that are limited when Mach3 is operated in Demo mode ).
and if not is it properly and fully implemented on Mach 4?
I have never tried it but if it's not fully implemented then it will be
and if so it is true that instead of running on an old PC through a parallel port I'd need to buy and fit a 3rd party add on card to my 4030 contoller?
There is a Mach4 legacy parallel port plugin but there are Win OS requirements
http://www.machsupport.com/shop/parallel-port-legacy-plugin-for-mach4/A motion controller (such as the Warp9 ESS but there are many different makes available to choose from) is, I think, the best option when using Mach4
That seems like a whole lot of unnecessary trouble and expense to go to for complete home NC novice to have to put himslef through just to get cutter comp that works.
Maybe
Tweakie.