Primary Use Cases diagram for ebXML Registry

I did this for a recent presentation and thought this may help explain 
to folks how ebXML Registry can be used:

    http://ebxmlrr.sourceforge.net/tmp/primaryUseCases.gif

Please share your thoughts and suggestions. Also share how best we could 
leverage the final form of this diagram to
educate people about ebXML Registry. Thanks.

-- 
Regards,
Farrukh