I believe MS is using artistic lisence with this. After all, he is definately using artistic lisence with the whole talking animals thing, lol. What if the moon chart here was showing us another ambigram/ same backwards as forwards thing...I feel like that is a definate recurring theme of the book. Why else would it be referenced with Dar, with the Chapter titles, with MS's name in the preface, and everything else? To me, it seems as if we need to examine the back of the book (the spells part) and solve that chunk of text. That has to be a major clue because he couldn't fit clues for all 100 rings in the rest of the illustrations combined! I see maybe 5-10 codes in the illustrations (no idea on how to solve them yet, lol) but my opinion is that the bulk of the rings locations (or whatever it is) is in the back of the book. However, I still am at a loss as how to explain the Red Hare Ring...
anyways, just some thoughts and ramblings!