Upgrade to the latest version of Addit! Pro. The latest version can automatically convert addons designed for previous versions of Flight Simulator.  The Addit! Pro Help file contains step-by-step instructions for installing Flight Shop aircraft and adventures. In Windows, press Start then Programs then Addit! Pro For Flight Simulator 98 then select Help. Double click on "The Flight Shop Converter" then double click on "Using the Flight Shop Converter with Addit! Pro".