Hi david,
I've installed all 3 megapacks and in both 2d and VC it's a fully loaded cockpit, looks like familar Boeing cockpit to me, don't appear at the moment to have any empty black boxes (not a pun

)
Double check you are copying the .dll file to the same folder where your fsx.cfg is.
The Effects folder to where fsx.cfg is.
The Gauges folder to where fsx.cfg is.
The Sounds folder to where fsx.cfg is.
The Airplane folder into the Simobjects folder.
regards
Steve
May the Mynd be with you.
So far my number of landings either passenger or pilot equal my number of takeoffs.
FSX Gold Acc, P3D V4, FS2020