Screenshot instead of artwork for iTunes movies

I've posted about this before, but with no reply. Surely, I can't be the only one who has this issue. Recently, when I download purchased movies on my Macbook Pro, instead of the proper artwork, I get a screenshot - like a thumbnail - where it should be. However, when I open up my old Macbook, and my iPhone, which are both authorized devices, the artwork is properly in place. Apple iTunes support has been of no help to correct this. Their only suggestion was re-downloading and this did not solve the issue.

Here are some pictures of what I'm talking about. Batman v Superman and Ip Man are the affected titles in these images: