Show "loading" indicator for Interactive Video
I'm creating Interactive Videos with some fairly large videos hosted on Vimeo, and in some cases I'm finding the videos take 10+ seconds to finish buffering and show within the player. During that time, the start screen title and play button show, but clicking on the play button simply makes the start screen disappear. This is obviously confusing to users, who then stare at a blank video player for a number of seconds until it finally starts playing.