PoserPro 2012 can internally create runtime hierarchy with all the fundamental folders.  Simply go to add runtime in the Library, and create 2 new folders anywhere you like.  The first folder will be the name of the particular content you would like to install, followed by a second folder within the first called runtime.  Click OK and Poser will create Camera, Character, Face, Hand, Hair, Lights, Materials, Props, Pose, and Scene folders.  Geometries and Textures folders will need to be manually created, but not an issue if you will be installing vendor content into those runtimes.