So...In this post I will briefly explain how to edit folders metadata and propagate these metadata changes.
Let's start saying that Folders_g component needs to be enabled in your UCM.
Propagation of metadata will affect child files and sub-folders contained in the folder itself. In this example I will update metadata of a folder named "D" so metadata propagation will affect both folders 2012, 2013 and all files contained in these two folders.
In order to propagate metadata first step is to select which metadata you wish to propagate.
Go to Administration -> Folder Configuration -> Information Field Inherit Configuration and select all metadata you need to propagate.
Now let's edit some metadata from our (existing) "D" folder. Click the folder you need to modify metadata...
...and choose Update.
After all metadata are modified you can propagate all changes down the "folder tree"
Please note that depending on how many content is stored "under" folders propagation process could take some time.
NOTE: As you probably noticed UCM doesent' have a folder structure as a common operating system.
It stores all contents in a "flat space" assigning a metadata to all files that are in a folder.
Metadata "FolderID" tells UCM that a file is contained in a certain folder. "FolderID" is automatically generated by UCM during folder creation, if not manually entered, and every folder has a unique "FolderID".
Folders themselves have "FolderID" metadata according to their position in the folder tree.
Top level folders have "FolderID" corresponding to the root folder which is Contribution Folders.