Hi,
that's quite simple, everytime the ball hit a brick, you increment a integer, and everytime you do increment it, you compare that integer with a value, and if greater you trigger an effect, AND you reset that counter ( else it would trigger that effect over and over again after that).
Does that make sense? The key to create easy systems like that is to fire a global event like "BALL HIT BRICK" or something, and then any fsm can listen to it and maintain it's own behavior, you could have several bonus based on different number of hits. you could also fire an event "BALL HIT WALL" and some bonus would then reset their counters etc etc.
bye,
Jean