I am also an aerospace engineer, now retired. I worked on avionic systems, particularly flight control. My Neurologist said to me once that he sees a lot of engineers who have developed Parkinsons- and has a slight feeling that we may be slightly more disposed to Parkinsons than others.
Regarding the arm swing, I have the same problem as you. When walking it is sometimes possible for me to "start" my right arm by consciously swinging it, moving my elbow joint not my shoulder.
Regarding the mouse- again like you I have problems with my right hand- and have actually switched to using my left hand for mouse operation, even though I am right handed.
Welcome to the Parkinsons "fellowship" on the forum.- best regards- Aviator