I've had this issue off and on for a couple of months now. Never with small files, but with the larger <300MB files. These larger files would stop somewhere in multiples of 10MB plus 0.1. So, 10.1, 20.1, 30.1, etc. was what I was seeing. They would attempt to go 10MB more a couple more times, then stop with error 8008. Any one file would stop at the same spot, but other files my stop somewhere else. So file Alpha would say stop at 130.1MB and it would always stop at 130.1MB. Beta file would stop at 240.1MB every time, and so on. Here are my experiences:
First time I was able to delete said file and continue downloading. Found the info here in the discussions on how to do this. No real biggy to fix. Fact is this happens a bit more than my liking, but acceptable.
Next time I had to contact Apple where they found the file on the server kaput. After about a month of trying every Sunday, the file finally downloaded. This was more of a pain in the butt because it took Apple a bit to repair the file. The tech support was mostly good. A pain because of the usual "Try this and that" before they tested the file and found it corrupt. Mostly good because I got the file after a month.
Last time (last couple of days) I could download some but not all files. I spoke with my ISP this morning and was informed they have an open ticket with Apple concerning their Akamai server. They gave me a new DNServer address and I was able to download flawlessly. This was certainly the worst experience. Not only did I have to put up with a overly confident tech who's abilities only extended to what Apple put up on her screen, but I had to actually discover the issue on my own with the help of my ISP. IMO if this ticket was offered to Apple then the tech should have known about it. Instead, I was told to try this, try that, oh well call Apple Support 'cause I can't help you sorry. The fact it was Memorial Day only exasperated the issue. For those who don't know, Apple has spread their Akamai servers around the nation (or world maybe) to help with loading. One of those resides at my ISP.
So the short version of this is I have had 3 different issues. Once with the download becoming corrupt, second with the Apple file being corrupt, and lastly with the Akamai server at my ISP having issues. If you are experiencing issues with downloads you may want to consider that I have had 3 different cases with 3 different repairs. I don't think this is a cookie cutter issue and you may want to try different alternative resolutions.
Hope this helps, sorry for the rant about the Tech.