The discussion here (After latest updates all images present in my project disappeared) was closed with more or less no result. I have a similar problem, related to embedded images in the blog template: images disappear from the project file, randomly. They are still in the resources window, the filename are present in the project file and there is a placeholder, but empty. As soon as one republishes all files, the images disappears from the rendered website.
Any idea where I should investigate?