ActionScript 3.0 :: Playing Frames Forwards And Reverse Via Button

I have a image gallery where you can click a foward button or a backwards one. I have each image on every 15th frame. So when the person clicks the next button it plays from 1-15 where it stops if they click back it will go to 15-1 etc. I got it working with the 2 images so I can go between them but when I add a third it won't do anything. I execpt it's something to do with removing the event listener, but I'm not sure.

Code:
stop();
var bRewind:Boolean = false;
this.back_mc.addEventListener(MouseEvent.CLICK, onMouseOver);
this.forward_mc.addEventListener(MouseEvent.CLICK, onMouseOut);
function fireEvent(event:Event):void{
[Code] .....