Sounds reasonable.
Just an off-hand idea: what about building something into the tool that will display a dialog box when you are about to download a non-GPL or unknown license car or track? There would have to be a "tag" or some kind of meta data to trigger against.
Or is this a much ado about nothin'?
Maybe another trigger to note that the car/track being downloaded is outside of the "vdrift sanctioned" set of cars and tracks? With any luck lots of people will be creating cars/tracks/configs of their own and there should be a way to let newbies to the game know that these data sets have not been vetted by the vdrift devs.
Just throwing that out there - may be something for version 2 of the tool.