Well the pictures 1-5, 7, 13-42, 46, and 47 don't even exist. Your HTML and javascript are fine. My guess is you haven't uploaded them to the server yet. This is the link to the very first picture that would be displayed,
>here<, as you can see for yourself, that they don't exist on the server. And this is a link to the first picture that you can see after clicking "Next Slide" 6 times,
>here<. Some photos are there, others are not.
8-)fffreak