When I use the GUI to add the directory
"/mnt/media/Video/Invader Zim", the core will stop reading the
argument at the first space character. So the core returns an
"Directory Not Valid: /mnt/media/Video/Invader". I think the GUI
needs to put quotes around arguments like this that are passed to
the core. I manually added this folder using the command client -
and placing quotes around it. It worked.