No matter how I configure the background inside of LR, slideshows that are exported and then played on other systems, the background is white and bleeds through and washes out the images. There are are also no settings as to control how the slideshow is exported (becomes a .mp4. It seems as though the only way to see the slideshow as viewed in LR is in LR. The export video seems to be worthless. I must be doing something wrong.