The Dimension3D script is still using the DSON Importer, it's just a different way to give it the name of a .duf file to load - with PoserCFs the Poser library file runs the python script which fires up the importer and tells it to load the .duf file (and then the library file may have Poser-native materials to apply to the loaded file); with the script it opens a file browser to allow the selection of a .duf file to load, which is then passed to the importer just as the Python script in a PoserCF passes it.