When running Claris CAD or MacDraw II (any version) on a computer with a Radius Pivot monitor, pivoting the monitor while the application is running can cause garbage to appear on the monitor. If you change the orientation before launching MacDraw II or Claris-CAD, the screen will appear correctly. This is because the off-screen buffer is set up based on the screen size upon launch.
This does not affect MacDraw Pro, because the off-screen buffer is set to the window size, not the screen.