I spent a lot of time trying to get the cube movement just right. It's physics-based and that makes it harder than if it were to just slide around (I considered it, but I kind of liked the rolling cube). I need to spend more time polishing that bit of movement physics to make it feel snappier I think. (And probably fix the sound effects as well).
Thanks for playing and your feedback! It's making me want to invest more time in this idea.