Image Thumnails only show on first menu item selection

My menu subcategory image thumbnails only show on the first option (Fabric - Cotton, Leather, Linen, Silk Wool). I have images uploaded for the sewing category as well (Accessories, Furniture, Machines, Notions, and patters) but these thumbnails do not show in the menu. You can see the images if you click the thumbnails and visit the category but not if you hove over the menu. My site is here

I can't figure out why my category thumbnails only show on the first category (Fabric). Any suggestions?

I looks like my template uses the plugin: CSS Horizontal Dropdown Menu. Don't know if that matters or not.

OK the images now show on the first category and third category. But the second category (and subcategories) does not show thumbnail images. 2 of those subcategories are documents only (not products) I wonder if having 2 document subcategories has anything to do with it. But the other 3 subcategory are still regular products.

Problem solved. Must have been a glitch that happened while creating the Sewing category. It was the only category that would not display subcategory images in the primary navigation menu.

Solution: I created a new category named it Sewing 2, then one by one moved categories over. Images showed perfectly. After emptying the Sewing category, deleted it. Then renamed the new category to back to Sewing. All is fine now. For some reason that ONE category just wouldn't display subcategory images in the menu hover. But now all is fine.