how to add movie artwork to iTunes 12.1.0.50
Hi,
I cannot add movie artwork to the latest version of iTunes 12.1.0.50 on Mac.
The movie was purchased outside of the iTunes platform and is in MP4 format. I can add the movie to the library and adjust the Metadata like director, genre, description, but when i try to add artwork it shows in the Get Info Menu, then when i select Ok, it vanishes.
I've tried the holding Option button as suggested in previous forums but cannot get it to work.
Any suggestions would be greatly appreciated.
Thanks
MacBook Pro with Retina display, OS X Mavericks (10.9)