I brought this topic up last week, then got distracted - I have also been having ongoing problems with custom permalinks...
Last year the galleryuccs.org site couldn't find post image links, but then it could if you changed the date for the post. Seemed like an odd work-around by the old administrator, but easy enough.
Then, the 2009 folder I made that has this year's images for shows was and still is impossible to find by wordpress.
The site uses the custom link formula of %category%/%year%/%postname%.
Also, on the post I'm trying to make where only name of the post's text shows up instead of the image, I copied the image location, and for the thumbnail it used the 2008 folder, and for the full-size it used the 2007 folder.