you need to elaborate more on whats not working. let us know what did and didnt happen and what changes youve made to your code. otherwise i have to try to guess at what youve done and the possible settings and things that could be setup wrong.
break down the situation/code into parts and learn what it does, how it functions. then debug step by step using print strings. dont just go by the line trace didnt make debug so it doesnt work and try something else. make sure the timer works, then make sure your getting overlap events, then move on and on until you reach the end.