Upgrading Directory Opus to 12.18 is not retaining the option to disable the "launch on double-click on Desktop" feature.
Preferences-->From the Desktop-->Double-Click on the Desktop-->Disable was reset to "Open the Default Lister"
Did you update from 12.17 to 12.18, or from an earlier version?
Is the setting not changing back now, even if you go to Preferences and change it, or was it only reset once after updating? (Neither should happen; just making sure we look in the right place.)
It was an earlier version than 12.17. I want to say 12.14 but I am unsure.
The setting can be changed and everything is fine now.
I also use Stardock's Fences program where double-clicking the desktop shows/hides all icons on the Desktop. I actually couldn't get a desktop after entering credentials because of the conflict. I had to use Safe Mode to reset things.
Hope this helps. Thank you.