3D XML Driven Carousel...Preloader?

I have this nifty little 3D Carousel http://www.expocadvr.com/temp/main.html which I learned to build at www.gotoandlearn.com

I would like to know if it is possible to add a preloader.

One that is visible while the xml images are loading…or one that hides the xml images until they are all loaded…either one is fine with me…any ideas?