GoogleEarth KML - embedded link handling

I’d like to use GoogleEarth for geographic presentation of selection options. Something along the lines of “Here’s a bunch of areas in which you might be interested - select one, click on it, and some useful things will happen.”

It’s easy enough to create a program that generates a KML file, and to fire up GoogleEarth to display it. The KML file includes placemarks; clicking on one brings up informative text, which can contain embedded hyperlinks.

The common result of clicking a hyperlink is to invoke a web page. But what I’d like is for the clicked link to cause data to be fed back to the program that generated the KML - saying, in effect, “Your user clicked placemark XYZ.”

Obviously, the hyperlink will reference something on the local machine. But what should that something be? An HTML file that runs a small JavaScript? A program that writes an argument to a file?

(I should perhaps note that I’m working in VisualStudio.NET 2005).

Am I allowed one bump?