It looks like the screens hook into something on the table and all of the registration is done by burning them on the screen in the same place.
I think the prayer at the beginning is what does the registration.
First erasable electronic paper - YouTube
not sure if this has been posted yet but it's worth a repost anyway
http://www.youtube.com/watch?v=Y9Ajb4omtac&feature=BFa&list=PLE2A 91FE6F09 7B48B&index=2
Crazy footage from inside a delivery van during the Japanese Tsunami.