Yes, I've since tried it with other FLAC files and lossy albums zips.
On Saturday and then again on Sunday I tried to download this album in ogg and mp3 format. The album's tracks seem to be complete when I extract and play them. Sizes don't quite match up with what's posted, but I figure that's just a difference in the way the website, browser, and file manager round out the decimal places.
Tuesday morning I was able to grab the entire FLAC file of this track. It was complete, sizes matched up, it played fine, and everything.
However, as a test just now I tried to download the album The Pony Empires Complete in mp3, like Sky Chaser. My download stopped after only 83.5 of 189.1MB, with no error message. Neither 7-Zip nor Windows can open the zip file, so it's obviously broken.
Then I grabbed the 27MB mp3 and 43MB FLAC versions of Twilight Sparkle's Mind Palace album, both completed successfully.
Finally, I tested the 90MB mp3 and 234MB FLAC zips of the Flutterwhat Returns album. They seem to be the right size and extract/play fine.
So it doesn't seem to be a totally consistent problem.
If you think it might make a difference, I'm also using Bell South as my ISP; probably in about the same region as Sky Chaser. I've been able to download large files from other sites (like podcasts and Linux liveCD images) without issue.