If you install Opus 9 over Opus 8 you may still see an Opus 8 icon on your desktop.
This is due to a bug in Windows/Explorer. It does not always notice that icons have been overwritten with different versions and continues to use the previously cached icon.
Rebooting may fix the problem.
Rebuilding your icon cache (e.g. using TweakUI's repair option) will definitely fix the problem.