with demo downloaded worked fine. After I installed DVDs pack and some scenery, now is not responding although aircraft is sitting on runway. Won't respond to mouse inputs. Have deleted it and reloaded it again same issue. I have a amd dual core processor 64 x2 5000, amd SLI motherboard, 8 gb ram, nvidia gt470 4gb card with 1tb hard drive. Please help, it's frustrating. It worked before in demo mode. Please email me.. Regards Ron.