Does anybody know how to set up an app for use in LiveWallpaper, like Shermans Aquarium and the other apps under the Unknown category?

I'm trying to get this gstreamer visualization as a Live Wallpaper:
gst-launch pulsesrc ! audioconvert ! tee ! queue ! monoscope ! ffmpegcolorspace ! xvimagesink

So I put that in a shell script, and then created the XML file that LiveWallpaper uses for external themes.

This shows under Unknown, but when I load it, it doesn't load in the root (background) window, but in its own window as usual. There is an attribute in the XML file (view) which I suspect has something to do with this.