If you want to install R20 on macOS 10.15 Catalina up to macOS 12 Monterey please be aware that you might run into issues if you have recently downloaded the installer. Of course, we were not able to test these versions back then against the new OS versions. First experiences show that once it's already installed it seems to work.
Note - It is no longer possible to install Cinema 4D R19 or older under Catalina/Big Sur because the installation programs of R19 or older were 32 Bit applications that Catalina/Big Sur no longer supports.
To allow you to install R20 follow these instructions
1. Download the installer.
2. Go to the search icon (Magnifying glass) and load Terminal.
3. Copy the following text between the quotations: "xattr -d com.apple.quarantine"
4. Paste this into the terminal but DO NOT PRESS ENTER.
5. PRESS SPACE
6. Then drag the downloaded dmg file directly into the terminal, right after where you typed. It should look something like this
"xattr -d com.apple.quarantine /Users/YourName/Downloads/Cinema4d.dmg"
(Make sure there is a space between the end of com.apple.quarantine and /users)
7. NOW press enter or return to start the command.
8. Try running the installer again.
Note 2 - It is no longer possible to install Cinema 4D R20 under macOS 13 Ventura. MacOS has introduced higher security restrictions for older programs, that prevent the installer from running, especially if you use an Apple Silicon system.
If you have your previous Cinema 4D installed on an older macOS already, you may be able to copy and paste the entire MAXON Folder from the old Applications folder of the old macOS to the new macOS.
We cannot guarantee the stability of older software, working on new hardware architecture than it was designed for.