TNCM Pushback vehicle and marshaller??

When I click the Customize button I get Settings - Display which has videocard hardware options on it. Nothing about traffic or ground vehicles.I have only these two setting screens that I can access:http://forums.avsim.net/user_files/154511.jpghttp://forums.avsim.net/user_files/154512.jpgNote that the sliders do not work properly for me, they won't visually move when being clicked and dragged and whatever the position the associated text does not change. (So the main sliders always say Custom and I have to guess the framerate lock by using keyboard keys to move it 20 presses to the right.) The preview pics next to the main sliders do change though.And as far as I can tell, the main traffic slider doesn't seem to do anything at all. I tried setting it at the minimum, saved a config file, set it all the way to the right and saved another config file. I checked the AirlineDensity and GADensity values in both config files via Notepad, and they were both at 21."Let me help you out. You're cleared to taxi any way you can to any runway you see."