How are FMP paths different in Catalina?

[animation_master]

I have a database that displays a movie in a container. I just provide a path to the video file, using:

moviemac:/VolumeName/Clips/name-of-clip.mov

Under Mojave, it works perfectly every time. Under Catalina, the movie fails to show.
Same FMP 19, same path, same solution, same files. The only difference is Catalina.
I have given FMP Full Disk Access and access to Files and Folders  in System Preferences.
Any ideas?
Thanks.

[Joost Miltenburg]

File Privileges come to mind. Same user trying to access the file?