First of all a word to the players: Think about this game as the "Bennett Foddy game of endless runners"...good, now go back and play it again :)
Now onto the review. It takes quite a lot of getting used to the controls, although there is not much to it. I had to think with "programmer brain" to figure out how the cube works. If you could make the cube into something that has a clear bottom and top it would be a nice help for anyone who doesn't understand why the cube doesn't jump properly (while it's upside down).
On the other hand I like the subtle things like the slowing down and jumping are the same action and you have to balance them to get to the next platform. Also the level design complements the player controls very well with the small bumps that you can fail on if you are not careful enough.
One more thing is that maybe adding a couple of checkpoints would benefit the game because getting through a hard part (albeit accidentally), then failing on an obvious challenge and getting put back to the very beginning was very frustrating at times.
All in all it's a great concept and with a better execution (subtle changes) would be an enjoyable yet challenging platformer.