I was having issues getting Bluecat's software to behave with C7 stuff (mostly issues with importing from 2.25). As a result, I set out to make my own deal... This is the end result. I have configured two Excel files for use on NA as well as a 1.8 PR (pressure ratio) setup. Why 1.8? Because the axis labels ended up nice and clean with that, and realistically, it should extrapolate past that point pretty closely.
How to use it:
There are two sheets.
COEFFICIENTS CALC
In this sheet, you past your VE table in the light blue area. The yellow area spits out your coefficients. Copy these back into your tune.
TABLE CALC
In this sheet, you can paste your coefficients in the light blue area, and it will generate the table with the appropriate axis labels. It's a good idea to copy the coefficients from the other sheet into this sheet and grab the table that's generated to edit.
I've attached to this post a couple of HPT files that run the custom operating system from Gen IV. The purpose of these is for ad hoc editing of the tables. Each table is set up with axis labels to mimic the pressure ratio found in the Excel files. You will put your table into here and apply your errors, then do whatever smoothing you want and copy it back into the Excel file. Every time you generate new coefficients, you should update this with your newly generated table (using the TABLE CALC tab).
This is not perfect, it uses predefined labels that I have picked, and doesn't necessarily try to blend zone edges. It'll get you pretty close though (and looking at GM's stock tables, you can see that it isn't a precision thing).
You will need to define custom histograms in your scanner that match the axis labels used in these files. You may also want to define a custom PID which is Pressure Ratio (should just be [PID.51]/[PID.11]).
Also, due to limitations on file sizes on HPT's forum, you will have to rename the files to .xlsx for them to work. If this doesn't work in Google Docs, well, I don't know what to tell you.