Developing complex dropdown menu

Hi,
I am working on a dropdown menu but am a little stuck.

I want to use the example for the complex rollover but am unsure as to where in the AS I need to add/modify so that the menu stays displayed until another menu option is chosen.

Here is the code:

 
//all this code is inside the complex button so you can stick as many as you want 
//on the stage and all will work.. they all will have this code in it..
stop(); // stop the movie clip from playing (stop button from growing, we want that when the mouse rolls over only
            
this.onEnterFrame = function(){
 if(rewind == true){   //if rewind switch is set to true play backwards
  prevFrame();        // play backwards
 }
}
this.onRollOver = function(){
 rewind = false; //set variable (or switch) that decides wether ot not to play backwards...
 play();    // play this movie clip.. (grow the button(tween));
 }
this.onRollOut = function(){
 rewind = true;    //set or rewind switch to true so it will play backwards...
 }

The example I am using is http://www.kirupa.com/developer/mx2004/button_effect.htm

Any help is greatly appreciated.

Thanks,
Joe :+)