I was hunting for a thread exactly like this and I think how gmtech explained it is so simple a lot of us do understand how he says do it. Thanks.
But I still must be missing something because - see my screen image below (If you haven't used the Snipping Tool, which is a default program/app in Win 7,8 or 8.1 - you might want to take a look at it). I took the two .cfg files in the 1st post above and downloaded and installed them on my workstation and started up VCM Scanner program and browsed to his .cfg file (notice I put his name after it so I know where I got it but made no changes)
Here is my explanation of all of my circles, highlights and arrows ... (I hope I can explain this so someone understands what my issue is, if not, sorry.)
I noticed it said "Cadillac CTS (V8) 2012 after the .cfg file which must have come from gmtech's .cfg file because I have never owned a Cadillac - probably means nothing but just wanted to point it out.
I think I understand the relation of the Chart Display to Chart Configuration to Insert Parameter / User Defined / Configure User Defined to Configure User Defined Parameters. See all the read circles and red arrows I did.
I'm wondering if I'm missing another file or something because if you notice that the BOOST (psi) is located in the Chart 2 under BOOST with a Label of BOOST and using a PID of Boost2. Since this is not a standard HPTuners PID then it must be a User Defined PID. If you look in the User Defined area with the read circle around it - there is no Boost2 PID listed. If I look at all of the User Defined PID (by clicking on the Configure User Defined) it isn't listed there either by the Boost2 name in the left column BUT if you click on #4 <undefined> it shows up there with the Name of Boost2.
For this discussion I not concerned why the Function has what it has.
Am I missing another file? If not, how does this work for you? Just an FYI, I did notice on the top chart on the 1st post of this thread that this field - BOOST (psi) has no value nor any line on the chart. Could be because there was nothing to display.
If you have question on what I'm talking about - ask away and I will do my best to answer it.
Sorry the display is so small in the post but if you open it up it is big enough to see. How to you make it bigger in the post?
Understanding Chart Display using gmtech16450yz cfg files.JPG