The REDCINE-X PRO application and the RED Apple Workflow Installer plug in are not notarized by Apple.
In the latest Mac OS (Mojave - 10.14+ & Catalina - 10.15+), the OS can only install notarized applications. When an application is not notarized, you must perform a work-around and click through a warning to allow the application to install.
After you download the installer file to your Mac, perform the following steps:
1. In Finder, right-click on the installer file. The Right-Click menu displays:
2. Click Open. A warning dialog displays:
3. Click Open to begin the installation.
For more information about safely opening apps on your Mac, please refer to this Apple Support article.
If the troubleshooting steps did not resolve the issue, please contact RED Support by submitting a Support request.