Loading External swf Issue

Hi There,

I am trying to load an external swf (Banner Rotator) to an existing swf (website).
My problem is that the banner rotator I am trying to add totally changes the display of my site which I had coded to resize to browsers and remain central.

Here is the live website before I have added the Banner Rotator:
www.samuelkarlbohn.com
and this is what happens to it after I add the code:
http://sarah-hammond.co.uk/sam_test/Testing.html

This is the code I used to load the external swf, it is within a an MC within an MC on the stage:

var my_loader:Loader = new Loader();
  my_loader.load(new URLRequest("PowerRotator.swf"));
  addChild(my_loader);

As you can see, the site is centred, and fits to browser window using this code: in the 3rd frame of the main .fla:

stop();
  import fl.transitions.Tween;
  import fl.transitions.easing.*;
  import fl.transitions.TweenEvent;
   
  var swfWidth:int = myStage.stageWidth;
  var swfHeight:int = myStage.stageHeight;
  var myStage:Stage = this.stage;
  myStage.scaleMode = StageScaleMode.NO_SCALE;
  myStage.align = StageAlign.TOP_LEFT;
  var main_mcYPos:Number = swfHeight - main_mc.height;
  var main_mcXPos:Number = swfWidth - main_mc.width;
  main_mc.y = main_mcYPos / 2;
  main_mc.x = main_mcXPos / 2;
   
  function resizeDisplay(event:Event):void {
              var swfWidth:int = myStage.stageWidth;
              var swfHeight:int = myStage.stageHeight; 
              var menu2YPos:Number = swfHeight - menu2.height;
              var main_mcYPos:Number = swfHeight - main_mc.height;
              var main_mcXPos:Number = swfWidth - main_mc.width;
              var tweenMenu2Y:Tween = new Tween(menu2, "y", Elastic.easeOut, menu2.y, menu2YPos, 1.2, true);
                          
  }
   
  myStage.addEventListener(Event.RESIZE, resizeDisplay);

The banner rotator is XML based, and has a folder called classes containing:
Banner, Main Application and a com folder containing some .as files for motion/dynamics. If this is of any relevance.

Has anyone come across something like this before, or know what I am doing wrong?
I am utterly confused as to how to sort this out, and am getting very close to my deadline (2 days away!).

Any help is greatly appreciated!

Many Thanks in advance,

Sarah