With an STFS Folder Import, the following information is obtained from valid files:

• Game Title (As the Xbox 360 saw it)
• Title ID (Required to use Continuum's game database)
• Game Icon (Saved to the IconData folder)
• Alternate Executables, including extra discs for multi-disc games and demos
• Cover art in an _covers folder, named "cover0.jpg"
• Kinect status (Used to warn about importing games that require Kinect, as Xenia doesn't have Kinect support)

Almost all of this is possible with a Manual Import, but all the data has to be provided yourself.  

First, click this button in Continuum (Under the "Add a Game" button):

You will be prompted to enter a Folder Filepath:

Heading over to File Explorer, this is the directory we want the path of:

Content files are inside these folders -- this is how files will appear off an unmodified Xbox 360. Do not change these folder names, but feel free to change the Title ID to any name, like how this example renamed the folder to "Forza Motorsport 2".

For reference, this is what the inside of one of these folders looks like:

And other types of content, like DLC or XBLA games:

Additionally, a folder named "_covers" with a file inside named "cover0.jpg" will automatically be imported with an STFS Folder Import.

Now, copy the filepath in the address bar. In the example's case, it would be "P:\360 Stuff\Content\0000000000000000\Forza Motorsport 2". You can paste this into Continuum with Ctrl+V.

This prompt will appear after entering the filepath. Click "OK" to continue and add the game. From here, you can adjust settings, or adjust them later.