NB These instructions are for GRAW 2 v1.02 and were published before the official release of a fully functional editor. At the time of publication, this is the only way to enter the GRAW 2 Editor.
Download this file and extract to your GRAW 2 folder.
Make a copy of your GRAW 2 desktop shortcut
Edit the new shortcut's Properties by adding a SPACE then the following text after the last quotation mark -o context-editor.xml
It should now look someting like this
"D:\Program Files\Ubisoft\Ghost Recon Advanced Warfighter 2\graw2.exe" -o context-editor.xml
This will now launch the GRAW 2 Editor.