Firstly your plugin is awsome this is exactly what i was looking for. there is only one point that if u can add it on next version will be Perfect for me and i thing for some others users. An option for facebook to be abel to define the default Thumbnails in case wher there is no picture on this post
Plugin takes featured image from the post. if there is no featured image it will take the first image from the post body. if your post body has no images it will take the specified default image. if default image is not specified it will take first image from the page.
Please set featured image to clearly define what image you would like to show or specify Plugin Settings->Other Settings->”Open Graph” Tags->Default Image URL for og:image tag for the default image.