Since the availability of Adobe Captivate (2017 release) Update 1, users have noticed that the autoplay play feature is no longer functioning in desktop browsers. This is actually more to do with changes in the browsers than it is with Adobe Captivate. The reason autoplay has been disabled is to prevent media from playing automatically in the browser. While this is good news when you are surfing the net and bombarded with multimedia advertising, it makes eLearning grind to halt before it even gets started. While I can’t solve this problem for you, I can show you how you can replace the blank white slide and boring play button with something more exciting and with something that looks more by design than what’s there now.
There is a bug in the logic for the image. If you import an image that is not used in the project, then when you cleanup your “Unused Assets” it will delete the image used on the cover. My hack for this is to add the image to a slide (slide 1 or the last slide and then elect to hide that slide during runtime. Needs to be fixed.
I noticed that as well and submitted it as a bug to Adobe. You should do the same if you haven’t already. They tend to focus on bugs and feature requests based on the number of people effected by it.
Looks like the SWF preview. Make sure you replace the image with one of your choosing and publish with HTML5. You shouldn’t publish using SWF any longer.