Problem when loading from a movieclip

1

I recentley looked at the tutorial on how to load images using xml in flash.

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

so far I understand that the images loads from the empty movie clip at its co-ordinates 0,0.
I would like images to load from the centre of the empty movie clip rather then top left.

Does anybody know how to change these co-ordinates from which the image loads from ?

thanks

tom