With the latest Mac OS X 10.4.3 update, Reunion users once again should have the ‘Virtual Plotter’ feature working.
Mentioned on the conflict page for Reunion 8: The Reunion item in the Settings pop-up menu of the Page Setup window has disappeared in Tiger (OS 10.4). This means that Reunion-specific settings described in the manual such as binding margins, fractional widths, and the Virtual Plotter are not available for use.
There was discussion of this issue in this thread on ReunionTalk.com as well. It’s recommended that if you are running Mac OS X 10.4.x, that you upgrade to Mac OS X 10.4.3 to correct this issue.