Stacking thumbnails in from XML in flash?

I have this simple xml photogallery script. I have 6 thumbnails and want to stack them 2 thumbnails in each row - giving me a stack of three rows (two thumbnails in each row).

Can somebody tell me how I can do this? I’m kind of stuck…

Here is my code in the flash piece ------ //

myPhoto = new XML();
myPhoto.ignoreWhite = true;
myPhoto.onLoad = function(success) {

numimages = this.firstChild.childNodes.length;
spacing = 70;
for (i=0; i<numimages; i++) {
this.picHolder = this.firstChild.childNodes*;
this.thumbHolder = thumbnails.createEmptyMovieClip(“thumbnail”+i, i);
this.thumbHolder._x = i*spacing;
this.thumbLoader = this.thumbHolder.createEmptyMovieClip(“thumbnail_image”, 0);
this.thumbLoader.loadMovie(this.picHolder.attributes.thmb);
this.thumbHolder.title = this.picHolder.attributes.title;
this.thumbHolder.main = this.picHolder.attributes.main;
this.thumbHolder.onRelease = function() {
loader.loadMovie(this.main);
title_txt.text = this.title;
};
}
};
myPhoto.load(“xmlphoto.xml”);

------------------------------------- //

Any guidance would be great. Thanks in advance.

_G