I dont mean to be mean, but dont look at iceking's response im not even sure what he is getting at (sorry iceking)
The first action is a if/then/else(multiple function). Its right at the top of the action list like 10 down from the top.
In the Condition section:
its a NOT a boolean like iceking said its a dialog button comparison. Set one side equal to last dialog button clicked and the other to one of your varible dialog buttons.
(MusicButton[1], MusicButton[2], MusicButton[3], ect.)
In the Then section:
THis is where you play the song
In the action:
Simply put a do nothing, first action on the list
THe second trigger just copys these lines per number of songs you have, so just copy these triggers down changing the Condition to a different dialog button and the THen to the correct music file.
Hope this clarifies everything