Perhaps you should choose a single category (like Gmail) of your Google content, download that, then go back and download another single category until you have it all.
Then I downloaded it and it went fine. So the problem is on Google's side.
The fact that I tried downloading the first archive so many times their service told me finally that I'd downloaded it too many times then the second archive failed around the same rough time frame. Their service is counting the failed downloads as successful, that's bad in itself.
