I love the idea of unlocking a song in the environment, especially with different styles for each area. I found it rather difficult to follow the prompts, especially with the circle appearing while I was still trying to watch the instructor's pattern. I can't really place it, but the tambourine also seems to have a rather awkward timing. I would have also appreciated a warning that new skills were coming in - I screwed up the entire first half of the owl's song because I didn't know about holding or the D key yet.
Overall... great concept - cute visuals - good audio (when it works: my first load didn't have any sound, and as you can see, others faced the same issue, but that may be a bug with the platform, as I've noticed it elsewhere) - interesting take on the controls, but needs some work.
The controls are so great, you've spoiled my experience with almost every other game on here. They're so well-paced and incredibly responsive. The game mechanics are such that it doesn't involve too much luck or a ridiculous amount of skill - it's clear what you should be doing, and takes a small number of repetitions to get the right pattern. The only minor complaint I have is that it's difficult to tell where the safe spot around a buzzsaw is.
I really like it, but I have one more suggestion -- some Link puzzles include a reverse tracking system wherein you can start from any point and drag to create a "note" (typically gray and/or dashed line), which would be very helpful in some of the puzzles where you know where you'd like to end up but not which color to start from. (Also a counter because I never knew when it would end!)
I would like to second the top comment wishing for a way to see through environment items, as well as a clearer way of marking exploded bombs, as well as gore opacity. I have died because I have incorrectly over-marked numbers due to an already exploded one being practically invisible.I have also been unable to read numbers due to trees or blood being in the way. It took me no time at all to complete Puzzles #1-3 but #4 has been murdering me left and right for over an hour because of an overabundance of zombies and the aforementioned UI issues with very few honest mistakes on my part. I would also like to remark that the angle of the board makes it slightly more difficult to tell which squares you are working with, so the addition of the "reveal" function for already-flagged numbers (like left+right click on traditional Minesweeper) would be a big help.
Ran into a bug where entering the stats room triggered a constant timer/achievement HUD loop. Timer would zoom in with "No Set Data 0:00:00" and then out and then zoom in the achievement count as "400/400" despite not having them all yet. Rinse and repeat forever... until restarting the game. Even leaving the room did not fix the issue. In fact, I even got two loops going at the same time at some point offset by a few frames.
GRAHHHHH the game froze, disabling the visuals and timer but keeping the sound and audio functions intact, interrupting my record-breaking Max Time run.
Minus points for having the "mark" look like a common alternate "X" and also for having to UNLOCK CONTROL PREFERENCES. Seriously? I have to play some way I don't want to and try to find the specific puzzle you've hidden this control option behind? Also, more mouse-friendly controls would be optimal. Like being able to right-click and turning off the keypad controls ("C" and "space" are very near each other)