I see, can you describe what exactly went wrong? The download from itch, installing, opening it, starting the game after opening it? Did you get an error report of the engine?
Hm, sorry. In that case I wouldn't know why you can't play the game. You did unpack the zip into a normal map and then execute the program to start, right? And you downloaded the one for your system, right? I wouldn't know if that would be pc or mac, but the pc one should work for most systems. If that didn't help, I too wouldn't know how to solve this problem. Do you experience the same problem with other ren'py games?