You have to press different keys to make the instruments work. Press the spacebar to hear the piano. Press the left arrow to hear the cymbals and press the right arrow to hear the guitar. The instruments also change to 6 different colours.
I used some the lessons but on some bits I made it a bit different for example when it said to the wait 0.126 I changed it a bit like I did 0.124 (something like that I think)
