Can't figure it out...

I'm sure I'm missing something obscenely obvious, but I just can't figure it out. :(

I used a script someone linked to a reply to another post I made a while back to display the contents of a directory. It worked. I modified the script by adding a couple of things and it works, but the images it used before stopped working. The script didn't come with any images (I think it generates them on the fly) and I didn't add or remove anything from it.

Anybody have any idea where I messed up?

The directory is http://quecojones.net/tmp/ and the script is called index.php. It shows up as one of the files in the directory listing.