I uploaded all the photos for a product, but it stays at “no image” for base, small and thumbnail. I’d have to manually set the base,small and thumbnail.
I think Magento should have set the first image as product image as soon as images are uploaded, the “no image” shouldn’t be default.
Via Store Manager you can export products to the file, import it back and in the process of import assign your columns with images to columns for base, small and thumbnail images of database.
In any case trial version is free and you can give it a try. Let me know if it helped.