Override MetaData

I’m trying to override the MetaData used in Sapphire and have used the example found here:
http://appletv.nanopi.net/manual/overriding-metadata/

However, all that is overridden is:

Title
Description
Cast
Genre

If I click on Files/Movies located on the Finder then I get:

Title
Rating
Description
Cast
Director
Producer
Released

Am I doing something wrong or is Sapphire limited in what can be overridden?

One other question, if the above is correct then how do I include a poster when using Files/Movies on the Finder.

PS is there a better way to describe the Files item on the Finder?

Thanks for the help.