I have been using the Personal Edition for a number of months now and have been learning as I go. I love the program but have experienced a problem when I try to load a second 3D file while the first is still loaded. As there is no Close command, the second file loads on top of the first, which is a pain. Even if I close the viewport (using the Close button under the application Close button), when I load the second file, it creates "duplicates" of all of the parts/assemblies in the structure browser. To prevent this I have to close the application and reopen it fresh. Am I missing something, or is this normal?