oh, sorry, this is for win 7:
https://www.youtube.com/watch?v=wxIIskKmUQA

but at first ignore the file extensions and try step by step what we wrote. it shouldnt need experience to download and install a game. so if you downloaded all the files completely (it needs a while) it really should work.
if your internet connection is slow i would download file by file, not all togeather. good luck :)