I launch Finale 2007 and click MIDI -> Native Instruments VST Setup. In that dialog box, I click "Play Finale file through Native Instruments VST. Now, for Finale channels 1-16, I select "Garritan Personal Orchestra" and click "Edit..."
It pops up an instance of Kontakt Player, version 220.127.116.11.
How do I tell that instance of Kontakt Player that it should use ASIO to drive my Cardbus sound card? If it were a standalone instance, I would select "Setup" from the File menu, but this instance has no File menu.
You don't. Finale takes care of the communication with the audio driver, and you can't select, which driver you want to use, in Finale. Your only option, if you want to use the ASIO driver, is to forget about VST and run GPO as either stand alone or a VST plugin in an external VST host like Garritan Studio.