I used to not be able to play my own music when playing this game - that's why I quit - but I tried it again yesterday and now I can!
I played Monochrome II (third last level in the hard set, I think) and it was pretty tough, but was able to beat the score limit by a lot in the end. The level after that was also a challenge, but I did it, but now I'm at a stupid level called Lime Labyrinth. It's one of those thinking levels, and I'm not in the mood to think much these days... Anyway, very fun game, and I'll try to complete it now.