Default setting for video
For some reason, the default setting when you have added a video is to loop the video.
I have never added a video into a slideshow of photos and then wanted the video to loop.
I just want the 5 second clip to play once, and then the pictures continue.
Don't know that I have ever seen a slide show that featured a looping video.
Maybe we could get the default set to the way most people use the feature?
There are actually more slideshows out there with looping videos than you might think, particularly where video backgrounds are used. That said, we can certainly look into this request.
Note that a video layer remains visible until the last (layer) keyframe, which may extend past the end of the video itself. In this case, the video will freeze on the last frame until that final keyframe is reached, assuming the 'loop video' option is disabled. Moving the last keyframe to line up with the end of the video, in the "Animations" tab, will ensure that the video layer disappears once it's over.