I`ve compiled a flightplan saved it in "my documents" got the main RC 3.1 screen entered product key pressed register screen freezes up also most of the buttons aregreyed out, what is the problem,? can someone help please

sounds like the registration key isn't being accepted. you might need a new one, if you have changed your hard drive or you're using a new operating system or you have a new pc.email rick at [email protected] with your product id, and he'll send you a new keyjd