Bill, I don't believe you need a "routine" to run Avid's touch plate. You can just use Mach4's "Touch" subscreen. Here's a screen shot of the Mach4 screen:
Under the blue screen, see the button called "Touch." Also, see the 4 little boxes above it. The box corresponding to the way you added your probe will turn on upon contact. Pressing the "Touch Button" will open a screen where you set your probe feed rate, offsets, and execute various touch moves. It's all built into a Mach4 canned macro. Works great.
Here's a screen print of the Touch Screen:
The Avid Touch Plate is not special, in so far as the way it is set up and used. What's special is some macro and screen modification Avid did. Avid's is nice, but not needed. The generic Mach4 Touch screen will allow you to fully use the Avid plate. If you are like me, the only routines you are likely to use with any regularity will be the center finding (the circle above that looks like cross hairs) and the Z=0 function (lower right hand corner). I believe there is some info about Touch module in the Mach4 docs subdirectory. I recall reading it. I believe it is the TouchOffHelp.PDF file.
Hope this helps.
Gary