For any Mac users having trouble opening the game, here's what worked for me:
1) Firstly, you'll need to download the itch.io app in order to run the game. I tried using the Mac terminal stuff and it just didn't work. So download the app first.
2) Once you have the app downloaded, login to your account (or make one). Once you're logged in, the app is a little tricky, since it doesn't have a search bar for finding games. However, there is an address bar at the top of the app and you can paste the link to to the game in there and hit enter. This will take you to the game's page.
3) Once you're at the game page, there will be an option at the bottom to install the app. Press install.
4) Now, once its installed, you can open it. The text might show up in a different language that's not English. If you need the game to be in English, here's what you need to do:
5) On the game's home screen, you'll see a wave of water. Press the third button from the top of the wave (this is the settings button).
6) Then it will take you to the settings. Look at the left hand column of the screen and press the third button from the top again.
7) Then look at the right hand column of the screen- you'll see a button that says 'English.' Click on that.
8) Now everything should be in English! And the game should be playable. Let me know if it works!