Currently there is not any option to have more control over the background video. We may add that in the future. Thanks for the idea!
If you are interested in doing some custom code, we will be adding several more attribute variables to the actions that we have placed within each of our components soon. Read more here if interested: https://aesopstoryengine.com/developers.
So, until then, what you could do is customize the chapter function to suit your needs and place it into the Code Snippets plugin.