Other people have helped me identify the cause of the problem (quarantine attribute on the app folder). I've uploaded a new dmg image. If you try to download it again it should work this time (I hope).
I don't really know Windows 10 but apparently it's available on ARM processors. The version available on the website will only work on x86-64 processors. Could that be the reason why it doesn't work?
I have just tried it on my older Mac that still runs El Capitan. I downloaded the image from the website, opened it and copied the folder to the desktop. I had the same error as you ("Skov is damaged and can't be opened"). Then I went to System Preferences > Security and Confidentiality and I saw that "Allow applications downloaded from" was set to "Mac App Store and identified developers". I selected "Anywhere" and tried again: it worked. So the problem was really Gatekeeper.
(1) & (2) The code is compiled using the Factor compiler so it really works like Factor
(3) Dynamically typed, type errors will be caught at runtime
(4) You use "while" and "until", you can see an example in the last screenshot in the web page
(5) There is a lambda. There are several examples of this on the web page, including a lambda inside a lambda