Found it: (
http://www.tweakguides.com/BF2_6.html)
"Playing Back Demos: To play back a custom-made demo in Battlerecorder, you must copy your demo into the \Documents and Settings\[username]\My Documents\Battlefield 2\Profiles\Default\demos\ directory (if that directory doesn't exist, create it under the Default profile directory). Then when you go into the Battlerecorder section of BF2, you will find that the demo is listed under the 'Battlerecorder Library' area, and you can simply highlight it and play it from there. Thanks to Ryan Nichols for this tip."
Hope that helps you out.