I really like this sim, but when I upgraded to XP it had the common compatability problem often discussed. After I changed the properties for compatability, the game almost worked. The only problem I had was that the "pilot" is now always looking up; almost like the keyboard is stuck, but I know that is not the problem. I am running a 1GHz Intel Celeron processor, the same one I used when I had Windows ME and the game worked fine. The problem was imported with the upgrade to XP. Any others have some ideas or same experiences?