I have 15 images in my gallery and only 14 of the thumbnails appear in the popup window when I hit the gallery button. If I use the pulldown menu, all 15 file names are there, and everything works fine.
If I type in the name of the missing image, the thumbnail appears all by itself. Choosing the image will work fine, but if a user doesn't see the thumbnail, they won't know it's a choice.
All images are jpegs and are about the same file size and format.
Any ideas on why this is happening?