Can a video or animated PNG be employed as virtual background?
Yes… That is how I attend all my online meetings… with a video background that makes me look like I am sitting in a busy restaurant, chatting to Chewbacca in the Millennium Falcon, in a busy coffee shop with people moving about behind me, at a beachside bungalow with a fireplace and the waves crashing in the background, etc.
The only downside is that you cannot apply a slight blur on a virtual background (only your real background), which would be add a nice bokeh effect on a busy or distracting video backdrop.
Is it possible to make the video backgrounds loop?
Sure, use the Video Playlist settings to do so: https://help.manycam.com/knowledge-base/manycam-video-playlist/