I have double triple checked everything, also I placed a "panel" folder and the aircraft are showing normal at the aircraft selection menu. No traffic, no stationary aircraft, nothing!
The simulator is building also the traffic when the traffic file is placed at the "World/Scenery"(saved for P3Dv3) folder.
I am not sure for all but some off them I have tested they work. As I said, with a panel folder inside they are selectable at the simulator menu. Something else is wrong but what!
Sounds more like an AFD or wingspan value issue to me then, because the HTAI payware Cessnas work fine in my P3D 3.4.
Did you check if there is parking where you want them to show up, that there is no duplicate AFD file and that the Cessna doesn't have a wing_span value in the aircraft.cfg file that would result in them not being able to park in the available parking spots? I'm assuming here that you already checked for a rogue FS9 traffic bgl.
I have check the wingspan values etc, other HTAI payware with the same values, for example the
"HTAI Cessna 172RG Cutlass RG" are showing as they should.
No issues with AFCAD either but as you said, I have found at the "aircraft.cfg" this,