I had a problem with it loosing where the gif file was, and looking for it directories that didn't exist, I think it is because I have spider friendly URLs.
they would appear, then I would go to a different page in the forums, and I would have red Xs,
it was looking for it here, http://www.vannin.com/threads/ubbthreads.php/ubb/snow.gif
- that folder doesn't exist.
to solve it, I added the following to my .htaccess
RedirectMatch 301 ^/(.*)/snow\.(gif) http://vannin.com/snow.gif
so all calls for snow.gif get redirected to the one in my root folder.