In the builds folder, go into the most recent folder and run the .exe or download the .zip file and get the .exe from there. Alternatively, you can get the .zip files here https://drive.google.com/open?id=0B1fQTHk_lCKCYlVHT3dPYWcxcjA
You can press 1, 2, 3, or 4 to load the respective stages if you cannot handle the full experience of the game :)