Hi,
First step. You do need to watch as much videos (
http://www.youtube.com/playlist?list=PLC759306A1E692A10)and studies the samples provide very carefully, so that playmaker concept has no secret, you must be comfortable with the FSm concepts, states, actions, transitions, events, before you dive into making this application.
Instead of replacing objects, I think you should design a flexible object, able to accept a particular reference to pla when it's ask to.
I would also cut down the problem into much smaller chunks:
1: are you able to design a grad a drop feature, meaning, you click and drag and object, and you are able to maintain the reference of the dragged object, and when releasing on another object, you can tell it which object was dragged onto it.
for this, in playmaker you can implement global events such a "MOUSE UP", there is even a "MOUSE DRAG" global event for you to use. So start by creating a fsm that can drag an object, first task, once you have that, working, work on the release aspect, that is create objects that can receive a drop ( all your 16 bits), then plug them together, the dragged object, calling the drop object, etc etc.
2: a "player", essentially playing the 16 sounds at a given tempo.
This one is easy, either you give the ability for each object to know when they have to play, or else you build a manager telling them objects when to play. So choose one technic, and then cut it down: can you call an object at constant interval, then how do you switch to the next object, etc etc.
This sound anyway a very good example for using my ArrayMaker addon
which essentially would make the mainteance and access of the various objects a lot easier.
https://hutonggames.fogbugz.com/default.asp?W715 Bye,
Jean