Glad to see your comments! I'll continue to update as I refine the settings.
All told, cost has been pretty much $1800. which includes $55. for the inspection & stickers, various extra parts etc. That's at least $700 less than if I'd gone to Eco-Shot (not to mention the time and fuel to get to Chilliwack). Any of you can do it for less just by duplicating most of my install - primarily the tank which I paid to have mounted. Once everything's more or less in place all you'll need to do is pay for an inspection.
When I have settings for my 4M40 I'll post them too so this whole thing will, hopefully, become something anyone can do if so desired.
Lowering & then incrementally raising propane volume is not referred to in directions per se. But it just makes sense and is confirmed by info Luna-Sea found online.
As far as actual measuring of propane etc. goes... just added and unnecessary complexity.
There's essentially two adjustments on the Powershot 2000/eCo-shot units;
-1) "Start time" (level of boost at which propane begins to flow.)
-2) Propane volume. (Initial volume of propane flow.)
From that starting point volume is increased commensurate with additional boost to a maximum of 15 psi, AFAIK.
It's designed to be effective with minimal complexity.
By comparison there are some systems which synch up with a vehicle's sensors and computers and get very complicated... and expensive. It's interesting that the guy I found to do my tank install and inspection, Arie, is currently having someone else equip his own diesel truck with one of these other very sophisticated computerized P/I systems. Although he owns one of the more established LPG and CNG conversion shops in the area (25 yrs), he had never heard of the Powershot 2000 or eCo-Shot.
Incidentally, Arie said he'd be happy to do more work with these if anyone needs help with any aspect. Much of the install can be done by a competent do-it-yourselfer. Other aspects would be worth getting qualified help with, at least for many of us. For example, the remote fill valve installation could turn out pretty ugly if done in someone's driveway and without the benefit of experience.
The above is based on my understanding of the thing but I am by no means an expert. If any of you come across further details or data on the Powershot, please add them to this thread.

I'm here to learn.