did you see? they have c# example of how to use the .dll
so get this demo to run, then get a vvvv plugintemplate to run and merge the two. without having looked into it, this could be quite trivial.
if you have troubles on that way ask specific questions.
I used it as normal (mono-)touch with vvvv (via mouse node). It worked very nice and the touch resolution was much better than with similar sized IR-touchframes.
In duo-touch mode i only tested it with some demo apps that came with the display. After testing these apps i can report that the touch frame really only is duo touch. And even this is not really reliable. If you touch the frame with two fingers at the same time (what the normal user often does) the display is not able to detect the two points properly.