Need help adding click events to a simple slideshow flash

Hi, I downloaded the trial of flash cs4 and have created a simnple flash
This is my first time,

I am creating a simple slideshow, each of the slides should be clickable
and redirect the browser

I created images then imported them and they were automatically converted to symbols
I combined the symbols using some motion tweens

I then created an actions layer and created clasic tween wher I want the user to be able to click.

My problem is I cant get it working. I think I am not referencing the right objects

here is the code I am inserting in to each tween on the actions layer

object.addEventListener(MouseEvent.MOUSE_DOWN, mouseDownfive);
function mouseDownfive(event:MouseEvent):void {
navigateToURL(new URLRequest("/myurl"));
}

I have tried setting the object reference to the motion tween instance name, the classic tween name on the actions layer and the symbol name

none seem to work

Any help is much appreciated, I have searched everywhere but cant find the answer

Thanks