Since it is a simple .zip file, Windows can open them by itself. You should be able to double click on the archive file and open it up and then drag folders into the game's directory. If it doesn't, I recommend updating 7zip, since I have created the archive using it, then right click and select "Extract here". Let me know if any specific error messages pop up. FYI: I only tested mod on Windows machines so not sure how it will react on others.