Version 2.2.0.1908 (Milestone 7) has just been released with everything needed to make and distribute First person, Top-Down and Open-World games
Hi! That was my fault, I forgot to ad-hoc sign the app. I just uploaded a new macOS build (1909) that should work - please report back
and thanks so much for your interest!
macOS Instructions:
Download and unzip
Right-click Fio.app
Click "Open"
macOS blocks the launch,
Go into Privacy & Security and click the "Allow" button on the section that shows that the app was blocked.
Don't forget to check the wiki: