It sounds like a problem with the template using the Thumbnail image arrangement (my favorite). My best guess without seeing the code is some type of tag or code conflict that is preventing the lister from working correctly.
If you can post a copy of the template, it might give me and others a chance to spot any obvious errors. You can copy and paste the HTML code to the practiceboard website and post back the link it provides, when you use the "see HTML" button.
http://www.practiceboard.com/
Danno