Mmm,
So if you need an immidiate response for the change, I revert to my 1st solution - activate the EventSender service for recording all changes, then develope a Windows Service which will check SEVT table every few seconds ("Listener" process) and activate the HTTP call if needed ("Action" process).
The basic idea of the service is to seperate the "Listener" process and the "Action" process. If you develope using Visual Studio, this can be easily done by implementing the
BackgroundWorker component.
Beni.