Sure thing, Rod. Here you go:
I don't publish to the directory in the screenshot: I always publish to the project folder I'm working with. As a follow-up, I exported all the video segments from the project back to the project folder and copied them to the video source folder for the project. When I republished the project again, all video files but one went missing again. The project did publish correctly, and I've tested it in our LMS. Only the video segments went missing. None of the image files were affected.
I will be starting a similar new project today or tomorrow, so I can keep a better eye on it.
Thanks for all the help, Rod, and for what you've given the greater Captivate community!