For all favorlist editor (Screensaver/Flash/Photo/Music), they have all the same
operations and UI as follows.

Name -- the name of this list, just for yourself to identify
Description -- the description of this list It is optional, you don't have
to enter it.
The list box contains the items in this list, they can be files or folders
Buttons
Add Items -- click to popup a sub menu, you can select to add files manually, add
a folder, or add files via a search box.
Delete -- remove the selected items from this list
Clear -- remove all items in this list
Move up -- move the selected items upward
Move down -- move the selected items downward
Save -- close this editor and save the modification
Cancel -- close this editor without saving
Preview -- click the preview the selected item
Notes
In the plan setting, you can customize to load these items sequentially or randomly.
Running sequentially means it will play the files in a favorlist as you specify,
so if you tend to do that, you should sort your file in this editor.