Hello SunUK,
Posting here is a good place for your questions.
Do you really have a PV750 or do you mean PV780?
We have several resources you might want to look at.
The Standard and Examples forum
viewforum.php?f=26 might have some helpful ideas.
If you have a PV780, the 2.7 reference manuals are here:
viewtopic.php?f=3&t=932
The PV750 was last supported in the 2.3 version of PowerVision Configuration Studio, the reference manuals are here:
viewtopic.php?f=3&t=583
You might be able to search this forum for "touch" and find some ideas about how to add a touch widget and use it.
The standard configurations included in the PowerVision Configuration Studio all are setup to receive the SPN 190 engine RPMs. Even the blank configs have this parameter on the Engine Device to receive from SourceAddress 0. If this is not the parameter you need to display, you can use the SPN 190 as an example.
This is probably more information than you really want, but maybe something here can get you started. If you get stuck, come back. I'll be glad to help.