Reported by straydogstrut from Discord.

v1 simply shows a macOS error dialog saying "ctjs" is damaged and can't be opened. You should move it to the trash with only the option to do that or cancel.

And by Djus:

all three mac users got the mkdir read-only error upon creating games (which where solved with the workaround from the forums with the EMPTY gamefile from Dropbox, but as they followed the spaceshooter-tutorial and presses "Play", they got a similar error. This was solved with the workaround from @straydogstrut by opening the nwjs file directly (not running the ctjs.app directly)