KALLEDEMOS'S PROFILE

Ummmm... I have a HUGE problem/error on the prologue. I can't get past the tutorial part where it tells you how to break bricks with bowser. the instruction says "wait until z pops up and press it with good timing." I tried everything; i 'pressed' it with the mouse; literally pressed the z button on my keyboard; and even went to the controls look at which button had the 'z' function and it didn't work. the field action button didn't work either. please help; because i do wanna get further. and btw i pretty sure i had the timing perfect.