Not answered to my satisfaction either.
I've done JS, CSS, html, 1-2000 lines of VBA for Excel and I just don't get the back & forth of adding a section to my doc to contain all the envelope BS, then modifying, then saving back to doc or dotx, then re-opening and trying again.
If I add to my doc, now I've got two areas/sections in doc with the address info
What a MESS.
Given that MS stuck it right up there in ribbon for 000's of users to get at.
I've downloaded Kenyons zip (notice I refuse to use the word "template"), and will look at it later today.