Hi,
Passenger density is at default setting.
I think I found a possible explanation for the choppiness - At ENSB, the ground was covered in snow and the vehicles / people had stuttered movement. When I loaded up at another airport (payware ENTC) - the vehicles and people were moving normally (ground was dry).... Who knows.
As an aside, when I edited the passenger pathway in the jetway from the terminal to the aircraft, the number with the height of each waypoint remains visible when the simulator is running.
I'll keep testing it out.