I'm confused, because I downloaded both of your files, and I'm showing the John's Version is already on that custom page size.

The spacing is also inconsistent. The top of Trent's Catechism is paragraph spaced at 1.25 and the remainder seems to be single spaced.

I use "Reveal Formatting" a lot for looking at text I didn't create. It's SHIFT + F1 in Word for Windows; not sure if that works for Word for Mac.