Okay, so after you have installed winrar, you have to right click on the .zip file you have downloaded, not winrar itself. There will be some options under Open, being "Open with winrar", "Extract files", "Extract here", and "Extract to ****(something)". Click Extract here as shown as picture. It will take some time and extract it. After it is done there will be a exe file somewhere. Open that, and I think you should open your game!