[Plugin: The Welcomizer] Barely Works

This plugin is fenomenal.
However, I get these errors in the wp-admin section of the site:
Uncaught TypeError: Object #<HTMLDocument> has no method ‘observe’ (from the console)

This(I think) prevents me from saving after editing and from looking at the library items which I assume open in a jquery powered lightbox of some kind.

http://wordpress.org/extend/plugins/the-welcomizer/