I am having this issue in MFSF24. I just bought the plane and the only way I can start the modern with avionics that has the red starter pull is by starting on the runway. The starter is not clickable and CTRL+E will not start it either. The classic that has the small red button works and will start. If this plane will not start and is still broken then I think a refund is in order. This thing has been out a while and should not still be having this issue.