ManiaCCC it seems your XComGame.exe is still compressed. You have to repeat decompress.exe -lzo XComGame.upk step.
Successful decompression process' output is similar to:
d:\XCOM Enemy Unknown\UPK\Compressed>Decompress -lzo "Patch 4 XComGame.upk"
Loading package: Patch 4 XComGame.upk Ver: 845/59 Engine: 8916 [FullComp] Names: 30044 Exports: 50729 Imports: 1883 Game: 8000
Patch 4 XComGame.upk: uncompressed size 12271863
Basically, you need to run cmd, then navigate to d: drive and with cd command (cd "Games\XCOM Enemy Within\XEW\XComGame\CookedPCConsole") to XEW's CookedPCCConsole. There you run decompress.
Edit: Forgot to mention decompressed files are placed into Unpacked folder
so please move them into correct location overwriting the compressed file and delete Unpacked folder.
Edited by Drakous79, 14 November 2013 - 12:29 PM.