Flash Navigation in storyline, MouseEvent.CLICK AS3

Hi everybody, my English is bad.... sorry..^^

My problem is very simple.

I'd like to use a flash file to create a navigation menu. In AS3, it's really simple to add Events listeners on my MovieClips... 

I am trying to change a variable in storyline by clicking on one of the items in my flash file.

I tried to use this :

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AS3 code :

var slide:int;

slide = 2;

function clickOnMyClip(e:MouseEvent)

{
  ExternalInterface.call('GetPlayer().SetVar','slideId', slide);

//slideId is a storyline variable

}

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But how could i listen the variable change in storyline (and see if i can get the variable) to jump to an other slide. Is it possible ?

javascript ? but How to write it and what listener can i use in storyline and on what event.... ^^

thanks for your answers.

best regards.

S.