Adding Thumbnails - XML & Flash Photo Gallery

[COLOR=Red][SIZE=3]Here is the link to the tutorial:[/SIZE][/COLOR]

http://www.kirupa.com/developer/mx2004/thumbnails.htm

I am pretty new to flash design, but all of the tutorials here are helping me progress rapidly. [U]

My question is, if I wanted to make the thumbnails in the above tutorial scroll up and down rather than from left to right, what would I do differently?[/U]

The help is much appreciated. Thanks!

=)