Thanks for all the replies. With my aptitude for goofing up, Capt Kevin, there are no stupid questions. However, yes parking brake on, correct parking space size, GSX L2 in use. What I did do was call up GSX’s customize aircraft, examined the details which were all correct, then checked the GSX folder in user apps. Shut down P3D, restarted and all worked perfectly. No idea quite why but happy with result.
Ron Harris