HKEY_USERS AppEvents on ControlPanel's Sounds and Audio Devices

I have a PlaySound code to play wav files specified in WindowsXP
registry HKEY_USERS\. Default\AppEvents\Schemes\Apps\MyApp\Pla
yIt. I
would like it to displays on the Sounds Tab of Sounds and Audio
Devices dialog, so the user can change to different wav file.  The
dialog only displays entries from HKEY_CURRENT_USER.  How do I do
about it?

Thanks,
Michael.