Sample C3PO to send email from Delphi application

I have a Delphi 5 application that integrates well with Outlook and Lotus Notes.  I now have a client that wants the same for Groupwise.  They're using Groupwise 12 (32 bit).  

What I want to be able to do is
1. click a button in my Delphi application, and using OLE Automation (must be late binding), initiate an email message
2. pre-populate some information,
3. turn control over to the user, allowing them to complete the message and click Send
4. Trap the Send event (or sent event) and save the message itself to a file
5. attach that file to data in my sql database.

My guess is that the first part isn't difficult, because I can do that from within my Delphi application.  I just need to know what the Ole Object name is, what the fields are called to prepopulate, etc.

Does GW allow you to put custom properties on a message, as Outlook does?  I need to somehow tag the message with a couple of values so that the C3PO could "recognize" the identifier in my SQL database to attach it to.

If there's sample code out there for me to do this, that would be great.

Another hurdle is that I don't have a GW infrastructure installed so that I could test this.  

Any suggestions?