Alright! That worked. I put the entire zip folder in Desktop, then unzipped, then dragged only Game app outside the folder to Desktop. One minor error I immediately encountered while starting up the game was this however:
The menu showing New Shift / Continue showed for a few seconds then flickered to a black screen. But, I was able to simply reset the game and things are going smoothly so far.
Thanks for all your hard work and patience! Developing for Mac seems tricky for all the security and permissions stuff haha