highlight images not appearing, no error messages

I've been working on updating my personal website and was having no issues getting gallery to integrate into my new design (other than wrapper issues, but that was just a matter of time before they were fixed). Now however, I am having problems with gallery itself, more specifically highlight images. In galleries I already had on the site highlight images appear just fine but if I went to change it it simply shows No Highlight and no images appears, even after just selecting a highlight. I thought upgrading Gallery would solve the problem, however, nothing changed. New galleries create show all thumbnails but if you try to select a highlight in any album or subalbum, nothing appears.

It seemed to me that it sounded like an access issue, something like the images coudln't be written to the proper directory for highlights or something like that, but I'm not sure.

Any ideas? You can see the problem with my 2nd main gallery on my site.
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The following information is required to get an answer:
Get this information from the PHP diagnostic (in the configuration wizard).
Gallery URL (optional but very useful): www.simplyschwark.com/gallery
Gallery version: newest, 1.5
Apache version: 1.3.33
PHP version (don't just say PHP 4, please): 4.3.11
Graphics Toolkit: ImageMagick (tried NetPBM to see if problem goes away, no luck)
Operating system: Linux
Web browser/version (if applicable): IE 6.0 and Firefox (problems in both)