WordPress Javascript gallery

I’m working on a product page currently hosted here.

I’m using a the varal Javascript gallery because it got some nice features like loading images in the background, thumbnails and a a .active class.

It works great in Firefox and even IE, but not in Webkit browsers (Chrome, Safari). Sometimes when clicking around on the product page or when refreshing the Javascript fails and the images just pops up. I have tried creating a non WP site and it works great. WordPress somehow is creating this problem.. I have also tried adding the javascript links in the header, footer whit out success.

If you guys have a clue why this is happening it would be much appreciated.
Thanks, Anton