There is a P3Dv3 installer.  Use it.  A specific serial number is required for the installer as well as for the original product (DVD).

scenery.cfg file entries:

[Area.100]
Title=FS Global 2010 - Oceania
Layer=100
Active=TRUE
Required=FALSE
Local=D:\FSGX2010\oce

[Area.101]
Title=FS Global 2010 - Europe
Layer=101
Active=TRUE
Required=FALSE
Local=D:\FSGX2010\eur

[Area.102]
Title=FS Global 2010 - Asia
Layer=102
Active=TRUE
Required=FALSE
Local=D:\FSGX2010\asi

[Area.103]
Title=FS Global 2010 - South America
Layer=103
Active=TRUE
Required=FALSE
Local=D:\FSGX2010\csa

[Area.104]
Title=FS Global 2010 - Africa
Layer=104
Active=TRUE
Required=FALSE
Local=D:\FSGX2010\afr

[Area.105]
Title=FS Global 2010 - Antarctica
Layer=105
Active=TRUE
Required=FALSE
Local=D:\FSGX2010\ant

[Area.106]
Title=FS Global 2010 - North America
Layer=106
Active=TRUE
Required=FALSE
Local=D:\FSGX2010\nam

[Area.107]
Title=FS Global 2010 - Local Meshes
Layer=107
Active=TRUE
Required=FALSE
Local=D:\FSGX2010\LocalMeshes

The following files are installed

\PILOTS_Software\FS Global 2010\FSG.cfg
\PILOTS_Software\FS Global 2010\FSG_No_Flatten.exe
\PILOTS_Software\FS Global 2010\fsx_default.cfg
\PILOTS_Software\FS Global 2010\manual.pdf
\PILOTS_Software\FS Global 2010\Uninstall\Interop.IWshRuntimeLibrary.dll
\PILOTS_Software\FS Global 2010\Uninstall\Ionic.Zip.Reduced.dll
\PILOTS_Software\FS Global 2010\Uninstall\Uninstall.exe
\PILOTS_Software\FS Global 2010\Uninstall\uninstall.iss

The following files are renamed to *.bg_

\Scenery\0203\scenery\dem0203.bgl
\Scenery\0204\scenery\dem0204.bgl
\Scenery\0205\scenery\dem0205.bgl
\Scenery\0304\scenery\dem0304.bgl
\Scenery\0305\scenery\dem0305.bgl
\Scenery\0403\scenery\dem0403.bgl
\Scenery\0404\scenery\dem0404.bgl
\Scenery\0405\scenery\dem0405.bgl
\Scenery\0502\scenery\dem0502.bgl
\Scenery\0503\scenery\dem0503.bgl
\Scenery\0504\scenery\dem0504.bgl
\Scenery\0505\scenery\dem0505.bgl
\Scenery\0506\scenery\dem0506.bgl
\Scenery\0602\scenery\dem0602.bgl
\Scenery\0603\scenery\dem0603.bgl
\Scenery\0604\scenery\dem0604.bgl
\Scenery\0605\scenery\dem0605.bgl
\Scenery\0606\scenery\dem0606.bgl
\Scenery\0702\scenery\dem0702.bgl
\Scenery\0703\scenery\dem0703.bgl
\Scenery\0704\scenery\dem0704.bgl
\Scenery\0705\scenery\dem0705.bgl
\Scenery\0801\scenery\dem0801.bgl
\Scenery\0802\scenery\dem0802.bgl
\Scenery\0803\scenery\dem0803.bgl
\Scenery\0804\scenery\dem0804.bgl
\Scenery\0805\scenery\dem0805.bgl
\Scenery\0901\scenery\dem0901.bgl
\Scenery\0902\scenery\dem0902.bgl
\Scenery\0903\scenery\dem0903.bgl
\Scenery\0904\scenery\dem0904.bgl
\Scenery\0905\scenery\dem0905.bgl
\Scenery\1001\scenery\dem1001.bgl
\Scenery\1002\scenery\dem1002.bgl
\Scenery\1003\scenery\dem1003.bgl
\Scenery\1004\scenery\dem1004.bgl
\Scenery\1005\scenery\dem1005.bgl
\Scenery\1102\scenery\dem1102.bgl
\Scenery\1103\scenery\dem1103.bgl
\Scenery\1104\scenery\dem1104.bgl
\Scenery\1105\scenery\dem1105.bgl
\Scenery\1106\scenery\dem1106.bgl

 

Run the following from P3D folder

ren .\Scenery\0203\scenery\dem0203.bgl dem0203.bg_
ren .\Scenery\0204\scenery\dem0204.bgl dem0204.bg_
ren .\Scenery\0205\scenery\dem0205.bgl dem0205.bg_
ren .\Scenery\0304\scenery\dem0304.bgl dem0304.bg_
ren .\Scenery\0305\scenery\dem0305.bgl dem0305.bg_
ren .\Scenery\0403\scenery\dem0403.bgl dem0403.bg_
ren .\Scenery\0404\scenery\dem0404.bgl dem0404.bg_
ren .\Scenery\0405\scenery\dem0405.bgl dem0405.bg_
ren .\Scenery\0502\scenery\dem0502.bgl dem0502.bg_
ren .\Scenery\0503\scenery\dem0503.bgl dem0503.bg_
ren .\Scenery\0504\scenery\dem0504.bgl dem0504.bg_
ren .\Scenery\0505\scenery\dem0505.bgl dem0505.bg_
ren .\Scenery\0506\scenery\dem0506.bgl dem0506.bg_
ren .\Scenery\0602\scenery\dem0602.bgl dem0602.bg_
ren .\Scenery\0603\scenery\dem0603.bgl dem0603.bg_
ren .\Scenery\0604\scenery\dem0604.bgl dem0604.bg_
ren .\Scenery\0605\scenery\dem0605.bgl dem0605.bg_
ren .\Scenery\0606\scenery\dem0606.bgl dem0606.bg_
ren .\Scenery\0702\scenery\dem0702.bgl dem0702.bg_
ren .\Scenery\0703\scenery\dem0703.bgl dem0703.bg_
ren .\Scenery\0704\scenery\dem0704.bgl dem0704.bg_
ren .\Scenery\0705\scenery\dem0705.bgl dem0705.bg_
ren .\Scenery\0801\scenery\dem0801.bgl dem0801.bg_
ren .\Scenery\0802\scenery\dem0802.bgl dem0802.bg_
ren .\Scenery\0803\scenery\dem0803.bgl dem0803.bg_
ren .\Scenery\0804\scenery\dem0804.bgl dem0804.bg_
ren .\Scenery\0805\scenery\dem0805.bgl dem0805.bg_
ren .\Scenery\0901\scenery\dem0901.bgl dem0901.bg_
ren .\Scenery\0902\scenery\dem0902.bgl dem0902.bg_
ren .\Scenery\0903\scenery\dem0903.bgl dem0903.bg_
ren .\Scenery\0904\scenery\dem0904.bgl dem0904.bg_
ren .\Scenery\0905\scenery\dem0905.bgl dem0905.bg_
ren .\Scenery\1001\scenery\dem1001.bgl dem1001.bg_
ren .\Scenery\1002\scenery\dem1002.bgl dem1002.bg_
ren .\Scenery\1003\scenery\dem1003.bgl dem1003.bg_
ren .\Scenery\1004\scenery\dem1004.bgl dem1004.bg_
ren .\Scenery\1005\scenery\dem1005.bgl dem1005.bg_
ren .\Scenery\1102\scenery\dem1102.bgl dem1102.bg_
ren .\Scenery\1103\scenery\dem1103.bgl dem1103.bg_
ren .\Scenery\1104\scenery\dem1104.bgl dem1104.bg_
ren .\Scenery\1105\scenery\dem1105.bgl dem1105.bg_
ren .\Scenery\1106\scenery\dem1106.bgl dem1106.bg_