I have contacted MJF about this and they will look at it.
I have also tested different startup scenarios and found one that works every time I have tested it .
Just start P3D select your airport etc.. select the Q400 version you want to use and load the scenario.
Then when it's loaded make the plane Cold and Dark : turn of all power also ground power, external power sw. generator sw. etc.., of with ignition and condition levers to CUT.
Save this Scenario and restart P3D
On the startup screen load the saved scenario when it's loaded you might see the external power generator wait for it to go away, if it's still there after a few seconds then you have forgot the external power sw. (turn it of save and try again).
Now you can do a Cold and Dark startup.
Regards Widar
PS. I still miss some effects !!!