Dynamic Image Scroller

I’m trying to set up a looping set of images (which works alone), that load from a PHP file (which also works alone), but when I try to set this up I get the following error:

Error: A ‘with’ action failed because the specified object did not exist.

Here’s what I’m using:

myLoadVars = new LoadVars();
myLoadVars.onLoad = function() {
	var imgA:Array = [this.images];// ["one.jpg", "two.jpg", "three.jpg"] works
	var slideShow = new classes.fx.tween(this, imgA, 3, "horizontal", 400, 250);// the issue is this line I think
	_global.delayImg = 1;
	slideShow.move(10, 10);
	trace(imgA); // this also = "one.jpg", "two.jpg", "three.jpg"
myLoadVars.load("dynamic_content.txt"); // eventually PHP

Thanks for any help.