Adding a slide/image shows previous slide instead - imovie 11'

When I add a slide/image to a sequence of images in a project, instead of showing that new image, it shows the previous image stretched out. This happens only on some projects. Some projects were fine for a day or two, and then when I went to working on them again, I run into this problem when adding slides/images. I also cannot transfer the images to a new project to fix the problem. When I select them all and click "copy," nothing shows up when I tell it to paste them into a new project. Is there are a fix for this?

I'm REALLY disappointed with this product. My audio progressively gets out of sync the longer my clips go as well. And this is a common problem for a lot of people with multiple imovie versions.