Instructions
You need to add the last one part of the url link from youtube video in the snippets at the bottom of the page.
For example, from this url: https://www.youtube.com/watch?v=eRfY-TuW8DA, you are going to use just this part: eRfY-TuW8DA and add it in to the list of editable snippets at the bottom of the page. Once all edits are completed save the changes. To see the change exit the site editing tool and refresh the page.