Catalina Users: The 64bit version of Studio Artist works with Catalina for Still Images but not Video. We will have a fix available very soon.
If you want to use Studio Artist for Video you will need to use the 32bit version (Included in the download) which runs on OS versions from 10.4.10-10.14 (Mojave).
Parallels: If you have updated to Catalina you can still use 32bit apps using Parallels. You can read more here.
Dual-Boot Disk: Or you can create a dual-boot partition to run both Catalina and Mojave. You can read more here.
We are working on a fix for this issue and it will be available very soon.