I just performed a clean install of Big Sur and was unable to get the latest builds (tried 1.13.7 and 1.13.8) to to work.
However, I then installed 1.13.0 and then 1.13.8 and that time it DID work. the is something important in 1.13.0 that was removed or significantly changed in a later release that is preventing the security override checks from finishing.