Using a third party filter

Question

I am looking at a filter from a website, but having difficulties with it as I have never used filters before.  I created a folder on my desktop, and in this folder, I created another folder called myFilters.  In this folder, I placed the TwirlFilter file and ammended it so it was
package myFilters{
I then created a new flash file, and in frame 1, I went to the actions
panel, and added the code for one of their examples.This is simple code
package
    import flash.display.Sprite;
    import myFilters.TwirlFilter;
    import flash.filters.DisplacementMapFilter;
    import flash.display.Bitmap;
    [SWF(width="420", height="280", backgroundColor="#fef9fe", frameRate="25")]
    public class SimpleExample extends Sprite
        public function SimpleExample()
            [Embed(source='/assets/prickpearsm-420x280.jpg')]
            var image:Class;
            var img:Bitmap=new image();
            addChild(img);
            var twirl:TwirlFilter=new TwirlFilter(this.stage.width/2-100,this.stage.height/2-100,100,Math.PI);
            img.filters=[twirl.filter];
            //addChild(twirl.image);
The package has no name, as it is in the top folder, and I import the
filter correctly, or so I think.  If i try running it, i get an error
1037: Packages cannot be nested.  Not sure why this is, or if I am even
doing this correctly.  As I say, first time using a filter, so didnt
know what to do with it.
Do you know what we might be doing wrong?
Thanks
Nick

Answer 1

Originally, the SimpleExample file was just an AS3 file.  The problem was that with an as3 file, you cant go to Control/Test Movie, so i did not know how I would play it.  This is why I changed it and tried adding it to a timeline in a flash file.  I have seen many examples on the internet of things I would like to try, but all they provide you with is as3 code.  When I get this file, how am I suppossed to play it to test it out?  If you know the answer or could provide me with some sort of tutorial, this would be great.
cheers