I think they're instances. When I look into a PZ3, I see object references. Change the .OBJ file, and all instances in the scene will be changed too (on save/reload). But it doesn't matter. A prop or a figure is pure data, it doesn't have methods associated with it. And since Poser needs the geometry/mapping data to be able to display it, those will be loaded for every instance of your prop. So there is no advantage to be gained from using external .OBJs, at least not for the end user. It may have some advantages while developing your set; change the mapping of the .OBJ and all instances in the .PZ3 will reflect the updated mapping, for instance. Actually, the same goes for Flash. The data for every instance must be loaded, the methods are called from one single library. But a Flash symbol always contains methods, so using instances certainly has an advantage in Flash.

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