Yeahhh the timing is really too fickle (you have to already be sitting on the right lane at the instant the beat changes, even if visually you were there a fraction of a second early/later).

That would definitely be an improvement I'd make with a bit more time

That's really nice to hear!

Thanks! Yeah the backing music is 12 bar blues, and the notes you hit are random notes from pentatonic scale for the chord that background is playing. 

I might put some more time into this at another point and improve the music algorithm and generally add some fit and finish