If you're bringing in the MacOS desktop via NDI Scan Converter, and you see the desktop without any icons present, this is related to the screen recording permissions in the System Preferences of the MacOS.
To enable Screen Recording:
-Go to System Preferences
-Under the Security & Privacy, scroll on the left hand side and select Screen Recording
-NewTek NDI Scan Converter should appear in this menu
-Ensure that the box is checked to enable Scan Converter to record the contents of the screen
Note: You may need to launch Scan Converter first and then go to the Security & Privacy menu.