I like the tech-docs approach:

1) issue a comprehensive printed manual in a 3 ring binder for the initial purchase

2) for revisions/upgrades, make available for download any additional pages to be inserted into the manual, and any replacement pages that supersede old information.

3) archive the incremental manuals for those who don't upgrade every time

4) page numbering system would have to be modified to accommodate insertions.
(section.page.paragraph , so the index might reference page 2.17.35)

It's not too bad printing a limited number of new pages for each upgrade. Not so convenient to print out the whole manual every time.

But, if you have EVER printed out the manual once, you can always use Adobe to print individual pages or ranges of pages from the new document and then insert them into your binder. But it would be a bear to keep it indexed.

An alternative would be to print out ONLY the section that you refer to the most. Much of the program is so intuitive that no manual is needed.. but if you find yourself opening the PDF every time you deal with a particular feauture, just print THAT out

https://www.dropbox.com/sh/ey71h8ep047758h/AAC12jNM0Hz9Q8zsh5iDeqNHa?dl=0