Here's what Tower Hobbies had to say about it:
If a customer wants to go from RealFlight Classic or Deluxe to
RealFLight G2, they MUST purhcase the full version of
RealFlight G2 or G2 Lite with the USB Interlink Controller.
* Because both RealFlight Classic and Deluxe have been
discontinued for more than an year, we no longer offer any
"upgrades" to RealFlight G2 for these outdated software
titles. ATS 12/11/02
Is there a way to get a hold of it or did I miss the opportunity to upgrade from RF Classic to RF G2 without buying the entire G2 package?