I can't speak for Github on how the download redirect works. If you'd feel more comfortable me uploading a zip to one of our servers, I can always put an alternative download link to our website. I just figured having it on Github with its source would be the most ideal situation.
But, I have no explanation to why you had gotten a weird different sized download.. that is strange.
As things turned out, I was hacked/RAT'd, less than two days later. So it may have been the intruder messing with the links.
Please post the correct file size and the MD5 and SHA checksums.