Showtime Slideshow quit working

I suddenly realized that my ShowTime Slideshow plug-in quit working. I’m not sure when this happened. I’m just getting a black box that never starts the slide show:

https://www.mijc.org/photos/2011-2/the-black-hills-south-dakota-05-2011/

I’ve read that permission errors can cause this; there were some posts vaguely referring to “setting folders to 755 and files to 644” but I’m not sure which folders and files they’re referring to. I’ve checked the plugins directory and the permissions are correct.

Any ideas here? I’ve tried deactivating and reactivating, and also re-saving settings.