I’m very sorry to report that the new update to macOS 10.15 Catalina, Apple’s new all 64-bit OS, seems to break all Mac plugins in the current Graffix catalog. Compiling plugins is much different from writing iPhone apps, so most resources out there don’t apply here, but please be assured that I’m actively working on it and free updates will become available.
In the meantime, there are a couple of things you can try. I won’t go so far as to say that I recommend this, but both have worked for me and for other users.
The site Der Flounder explains how to turn off Apple’s quarantine flag using the terminal. A variation on this technique goes like this:
1. Open the Terminal app and run the following command (in this example for Concatenate for CC 2019):
sudo xattr -cr /Applications/Adobe\ Illustrator\ CC\ 2019/Plug-ins.localized/Concatenate.aip
2. Enter your password if asked.
3. Repeat for each plugin.
Illustrator should launch and load the plugins normally.
I sincerely apologize for any inconvenience.