Good morning,
I tried to install TurbolenceFD (the latest version) on mac with Catalina and C4D r21, but once inserted in the ‘Plugins → TurbolenceFD → Dmg extracted’ folder I can’t find it inside C4D Extensions menu.
I have already made many attempts, but nothing changes…
thanks in advance for the help! 
Unfortunately support for Catalina is still unstable at this point.
Apple has introduced strict security measures in Catalina and its behavior has been changing with recent updates.
I’m hoping these issues can be resolved soon.
The new build 1458 now supports macOS Catalina.