Hey Paul,
I have done what your talking about if you need some help. I made 2 Programable automated "Target Ranges" that use Mach to control stuff through PLC's with a HMI touch panel. I have also used it to run some pick and place machines and some other non-traditional machine tools.
The users of the program/screens/system, have NO clue that they are using a Machine controller. I live close to Knoxville, TN, so if you want me to swing by and show you how to set up, and do stuff let me know.
Here is my email replace the "at" with "@" PoppaBear@hughes.net
Scott