If I interpret correctly, the CardRunner.dll is a service file that autoruns when you start your phone. What does it do? It is a location-based service introduced by Garmin Mobile XT. It attempts to integrate your phone contacts to the entire application. Where you can share your 'current position' with your contacts who uses the same application. This is where it sucks the battery because it will keep checking for 'Location based message' that could be sent by your contacts. Because of this, parts of the app will have to run and your GPS is active from time to time (I think).

Anyway lets see if this gives an improvement. I'm still testing this tip.