Are you using any popup blocker? It should download right after you click on "download" button. There is no "install" button on this page. The file size of the game(demo) is 132mb. People are being able to download it fine as I can see in my analytics page, so it's probably your browser.
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no. also im using the itch app. the language barrier is kinda probably messing with us. sorry about that. imma describe it as accurate as possible. downright is the button right next to another button which looks similar to an option like button. if i click on it it just doesnt show me how big the game is. even if i tried to continue to download it just says :(cannot read property "build" of undefined)