I have registered an imgbox account and changed just the main title picture on the BCS SE mod page as a test.
Please could a couple of you have a look at it and see if Chrome is happy to display the banner picture in the main body of the mod? If it does then I can start swapping over all the other embedded pictures away from my http: host to the imgbox https.
It is just the first embedded "Book Covers Skyrim Special Edition 1024x512" image. The smaller "About" and similar images are still from my old http host.