Nah, Gamersgate's downloader issue was a server-side issue. They took their South African servers down for maintenance shortly after I finally managed to get them to take a look at it.
The gog downloader, on the other hand, continuously pauses my downloads for no apparent reason. I've spoken to a few other people on their forums who experience the same issue, but nobody is really sure why it happens. Most popular theory seems to be that it pauses whenever something else starts hogging bandwidth (automatic updates, etc) or when the connection experiences a dip in download speed.