Sorry, I have a GMC-500, so it submits the data to gmcmap over wifi, so it's not linked the a computer (just plugged into USB power).
So only way I can think of doing this is have the counter submit to a script I host, that then logs the data itself, and turns around and sends the data to gmcmap as well.
Just think it might be nice to have a simple page for a counter that shows it's last update (datetime) and what the associated count was.
If you connect your detector to Radmon.org, there is a way to query their server with a url for any station's most recent value. Search their forum for "Google Gauge" to see an example of a graphical representation. The url is in the code example.