Can't extract files from the tarball

I feel kind of stupid posting this, because apparently close to 10,000 people have been able to do this with no problem, but I am having a problem extracting files from the tarball. I'm using 7Zip file manager. I can extract the gz file from the gz.gz, but nothing happens when I try to do the second extraction. The md5 hash is correct. When I test the archive with 7Zip, it says there are 0 files and 0 folders in the archive. I also tried downloading the 6x-dev version and had the same problem. Am I missing something or is there something wrong with the downloads?