Make a note of the folder containing the Runtime you want to add (eg, if you wanted to add the Gazebo, and you'd unzipped it so your had C:GazeboRuntimeGeometries, C:GazeboRuntimelibraries and C:GazeboRuntimeTextures it would be the gazebo folder you'd make a note of). Make sure you're showing the Poser content directories panel, click Add and click the +s until you reach and select, in this example, Gazebo. OK out and the folder should be added, and you'd be able to select the figure by going to +Gazebo+Figures+Sams3d. Having said that, you don't want a separate entry for every item - you're better off creating a few Runtimes (for types of thing, or makers, or periods - whatever seems a sensible way of spliting stuff down) and unzipping/installing all things that go under each heading to the same place. You'll end up with one Runtime folder in each location, and each Runtime will contain Geometries, libraries and textures folders, which will hold files from several different products (or in the case of the libraries folder will hold a set of library category folders with folders hodling files for different products).