Slideshow in Hueman

I recently updated to the latest version and lost the featured image slider in my Hueman theme. If I choose 1 featured post, the image will display at the top larger than the other posts. If, however, I choose 2 or more, the slider disappears completely. In the past, I’d gone into the featured section of the editor and change some code. But now that that stuff is all available in the customizer, I should be able to set that all up easily and have it work. Perhaps one of my plugins is getting in the way then.