Well I have added some of Agent Smiths buildings to my map. His addon was binarized and I just used the file in my res addon folder. When you place an object just click on the browse button and click around until you get into you addon folder. Then click on the .pbo file and it should show the p3d files. select the file you want to add, if you get a message like unable to load file or if it does not show in the preview mode then it is not binarized.