It works. I dragged some of them over from FS9 and installed the bgl files in the corresponding folder i.e. P3D\scenery\world (I think)
The aircraft I also dragged across only this time I created a new folder P3D\SimObjects\WOAI - then I edited the P3D.cfg file to include the new folder. e.g.
[Main]
DisablePreload=1
HideMenuFullscreen=1
HideMenuNormal=0
Location=341,30,1773,893,\\.\DISPLAY1
Maximized=0
SimObjectPaths.0=SimObjects\Airplanes
SimObjectPaths.1=SimObjects\Rotorcraft
SimObjectPaths.2=SimObjects\GroundVehicles
SimObjectPaths.3=SimObjects\Boats
SimObjectPaths.4=SimObjects\Animals
SimObjectPaths.5=SimObjects\Misc
SimObjectPaths.6=SimObjects\Submersible
SimObjectPaths.7=SimObjects\WOAI <--------- The new folder.
SimObjectPaths.8=SimObjects\Aircraft_Mil
SimObjectPaths.9=SimObjects\Aircraft_Civ
SimObjectPaths.10=SimObjects\Military AI
SimObjectPaths.11=SimObjects\Maltby
User Objects=Airplane, Helicopter, Submersible, ExternalSim
ProcSpeed=10218
PerfBucket=7

As you can see I have added numerous others too.

Where is the P3D.cfg file located?

Just a quick point on this subject. I use World of AI traffic in P3D. You should be aware that WoAI traffic files are in FS9 format. P3D AI works like FSX and it requires ALL traffic files to be in FSX format if you want to see ANY FSX traffic. In other words if even one traffic file is in FS9 format then the sim will ONLY display FS9 format traffic and not a mixture.

If you are ONLY going to use World of AI traffic that's fine but be aware that using even one WoAI file will disable the default traffic and any other FSX traffic. To get round this you have to convert the WoAI traffic files to FSX and fortunately this is quite easy using Don Grovestine's freeware AI Flight Planner.

Download it from here http://stuff4fs.com/newpage.asp?Folder=AIFP and familiarise yourself with the relevant instructions. You can convert them all as a batch. There is also an option to search for FS9 traffic files in your FS folders which is a good idea as there could be one little rascal hidden away somewhere and preventing your FSX AI from displaying.

Ian