Version: 1.30
Windows Version: 8(.0)
When "Modern UI Applications" is the first folder alphabetically in the list of folders displayed in "All Programs" by Start8[1], the Modern UI Applications are displayed oddly-- there is a "Modern UI Applications" folder shown, but it is empty, and all the Modern UI apps themselves are bumped up a level and shown directly in "All Programs".
So if you're trying to organize your start menu folder structure and none of the folders you have set up have names that alphabetically come before "Modern UI Applications", you'll get a jumble of all the Metro apps combined at the All Programs level with your folders and the applications you wanted shown at that level. The moment you add a folder with a name that causes "Modern UI Applications" no longer to be the first folder listed, all those Metro apps go back inside the Modern UI Applications folder where they're supposed to be.
I spent a while annoyed that the only options seemed to be hiding these apps altogether or showing them all directly at the "All Programs" level with no option to hide them in a subfolder until I happened upon the way that this odd misbehavior is triggered or not.
[1] That is, the combination of the user's [user folder]\AppData\Roaming\Microsoft\Windows\Start Menu\Programs folder and the shared [system drive:]\ProgramData\Microsoft\Windows\Start Menu\Programs folder.