I need help making an online gallery similar to this one:

http://www.marilynmanson.com/art/

From what I understand, there is an initial preloader (disregarding the ‘how do I look?’ intro) and then a sidescroller of buttons, which are thumbs of the paintings.

When you pass over them, they slightly enlarge. These are buttons right?

Once you click on a thumb a small preloader starts underneath and a larger image comes to the foreground. 

You click again and it goes back to the sidescroller.

I enjoy the simplicity of this flash gallery and how it does not overpower the work.

Any guidance would be greatly appreciated? 

How can I make a sidescroller of just the small thumbs while leaving the background the same?

How can I make small preloaders for each thumb and the larger image come up while the background fades to almost white?

Thanks everyone and have a great Memorial Day weekend