Site Origin Post Caroussel Widget – Problems when featured image is an external one

Hello,
First of all, thanks to do the plugin! it helps a lot!!
I am having some problems when displaying the featured image in the caroussel widget. I use another plugin to be able to use an external image as a post featured image (the reason is that I use an external server to store all images, but all of them have public access).
I don’t have any problem when I use the original widgets from all themes I tried, but when I try to use the caroussel widget, it does find the posts, but it doesn’t display any image. I am a bit lost on this… is there any CSS modification required or anything I should care about?
Many thanks in advance!!

URL: http://lauraroundthe.world