I've just added a feature that was requested a couple of days ago; to have an option to have the key names inside the notes. This turned out to be quite easy to implement, so it's now in the game! In the Graphics settings, you can change the note interior from "Classic" to "Key" to get this effect.
Another new feature is that your choice of settings is now saved instead of resetting each time you reopen the game! My dev friend told me players like this message more than saying "I fixed a bug where I forgot to comment out the debug code that resets the settings file for testing purposes".
Anyway the player who reported that bug also thought it'd be nice to be able to press space to pause the game (You could and still can use the ESC key to pause the game, but I think this was only tangentially implied in the tutorial). Anyway since the space bar wasn't doing anything else during gameplay, now it pauses the game.