Regarding the orientation of the final "word" (n15), here's how my logic for how it works:
The trick with Puzzle 12 is that its 12 "words" don't need to actually be words, they just have to be the leftovers.
All leftovers are read top-to-bottom, so the canonical leftovers include nonsense like "foec@rton" (f9). The leftovers are not the reversed versions like "deliver" (hence no "d7" clue). You can confirm this via the bottom-right hints, and also the bottom-left hints of puzzle 12. So for consistency, the bottom of page 12 must say "n15" just like it says "f8". *
The reason I did it this way is so that when the leftovers ( "reviled", "foecart0n", "nowevahwonuoysa", etc.) get written backwards on the right side, the result is a perfectly-readable left-to-right message that's hard to miss.
Hope that makes sense!
*unless I changed the bottom of 12 to have hints like "n8" for "notraceof".