From our understanding of the Jam's rules the game fits the criteria; the resolution of the game is 8x8 pixels including the player character, but if the full level's resolution is taken into account you are absolutely correct. In addition to this, we believe you may be correct about the player character; it does not seem like the player is bound to the same grid as the level itself.
Music is incoming! We were not able to complete it before the Jam ended; once judging is over, We will still be updating the game with music and more levels. We've also considered adding more movement options and interactable objects.
For level three, the trick is to hop onto the second ledge closest to the entryway and dash off of it, using X, onto the platform. If that level gives you grief, the next one may as well; in level four wall jump twice on the left and dash right to get over the spikes.
Thank you so much for your input! If you have any more issues with the levels, please reach out; We always reply to comments.