How to Get the Vintage Achievement
The solution is given on the very first page (you have to stand in water for 60 seconds to see it, as suggested by the star drawn there corresponding to another page), but you need to translate the language to read it. I did beat the game without looking up anything, but I made absolutely no progress in terms of that, and other than that treasure you don’t get much by translating.
The text is “The softest feather, corrected eleven times, departed once more” which corresponds to down, right x 11, left x 12
(The other one I had to look up was the one that requires you to bomb the wall because you don’t use a mechanism like that anywhere else in the game… I sat there trying to interpret the bushes as inputs for directional buttons for probably 2+ hours.)
Here is one of the absolute geniuses who figured out the “language” (it is a language, but that language is English — it’s just a different way to represent it.)