Could it be that I can't edit a maneuver node when MJ is active? I could not open it with ALT+N, the gizmo flashes on and off in a blink... - Edit: Now it crashed, I crosspost to Logs: https://www.dropbox.com/s/ze6xtn99so20qaa/2017-05-08-1 KSP.log.7z?dl=0