The oxahedron owl never triggered because it turned day while you were talking to it and it flew away before finishing the text.

Oh no, that QR map being in a chest right next to a pillar was such a red herring! The intensely-red platforming section is certainly not as complicated as it seems.

The make a cube puzzle is another obtuse puzzle for obtuse nerds. The tuning forks are made for people with rumbling controllers, (or good headphones) and everyone else is basically hosed! Ask me how I know! Did anyone mention this was the premiere game for the Xbox Live Arcade platform? Some of the secrets are linked to other secrets you haven't solved yet! In fact, you've been missing a big progression puzzle in the waterfall area.

The eight six-square shapes on that wall are cube nets. That is, they're arrangements of squares in 2D space that can be folded into a cube in 3D space. I think the puzzle wasn't solved because the cubes weren't all in the same plane when they were in the "right" arrangement. If that puzzle is meant to be _really_ hard, then it might be expecting the 3D net of a 4D cube, for which you'd need 8 smaller cubes. I was thinking that the purple pillar was a red herring and that you just happened to be stood there when executing the button sequence, but while typing this out it occurred to me that the _negative_ space formed inside the top of the pillars is a wire-mesh _cube._ Negative ... cube? So now I'm thinking that each pillar might have its own button sequence for an anti-cube.