Hi,
the autoplay and loop are enabled in the plugin. You can check it in other browser like Firefox. But, as you can check in the article there are problems with some browser versions that not allow the autoplay.
In the admin panel, you can only add the video ID. This option is used to complete the javascript code used to load the Vimeo video. I attach you the piece of the code where the video is loaded.
<div id="fullscreen-wrap"><iframe id="player1" src="https://player.vimeo.com/video/' + i.videoId + '?autoplay=1&loop=1&api=1&player_id=player1" width="500" height="281" frameborder="0" webkitallowfullscreen mozallowfullscreen allowfullscreen></iframe></div>
The variable i.videoId is the video ID set up in the admin panel.
Regards