I just had a similar problem occur with
my latest card. The original photo uploaded just fine, but then I realized I had the wrong SU set. I edited my photo and after I saved it, all I get is the title. Now, I can see it ok in my gallery but when I click on the thumbnail, there is no photo.
I'm going to go back and try to re-add the photo. There was a field where you could upload another photo but it said to leave it blank to keep the same photo. Maybe there is a bug in that code?