It's "not commonly downloaded" yet because until a few minutes ago it didn't exist. :-)

The "Windows has protected your PC" message is one I see often when launching installers and programs downloaded from the Internet. If you are unsure whether the file is safe, you should of course not run it. Windows is trying
to help avoid virus and malware attacks by warning users when they are about to run something that came from the Internet. However, the message is not itself an indication that the installer is infected or malicious.