Hello,
I don't know why but when I compile the game for Mac, the main file is no longer flagged as executable. You can fix this by opening a terminal then type :
cd [path where the app is located].app/Contents/MacOS
once you are inside this folder (since a .app is actually a folder) and
chmod a+x Dream-46
You can now launch the game but only with Right Click > Open. Since Catalina update, Apple is pretty straight now about non-signed executables.
Sorry for the inconvenience.