Photo gallery XML tutorial - grid thumbnails version?

I saw the tutorial here on how to make a Flash XML photo gallery with a scrolling thumbnail bar. Awesome!

The thing is, the example he DIDN’T choose to illustrate is the one I want make - exactly.

That is, the grid thumbnail layout (http://www.kirupa.com/developer/mx2004/thumbnails.htm).

Is there somewhere else I can find this? The problem is that I have say, 16 photos and I want 4 displaying on the stage at one time. I want a forward / back button available to switch through the remaining 12 images, when the user clicks the buttons (as opposed to a scroller, which I find difficult to control and therefore less useable).

The problem comes when loading the four images from my XML file. I am able to load the first four, but how do I indicate in AS that the next four images are to be loaded, until there are no more images left? What if I add 5 more, I want to be able to have that AS load them. I was using a mod function in my script, but I keep getting the wrong remainder. I’ll have to post the code later.

But does anyone know what I’m talking about, and can you point me to something that might help?

Thanks.