Xatrix' Ryan "Ridah" Feltrin updated his .plan with details on how the new download code that was implemented into Kingpin works. Here's what he had to say:

...what I did was break the file being sent, into "chunks" of 1024 bytes. This way the client can keep a record of which "chunks" it has recieved, giving it the ability to have multiple pending requests for data at once.Anyway, that's the basic principle. Some obstacles here were finding the right balance between sending too many requests, and not sending enough. This was handled by adjusting the maximum number of pending requests with the current RATE setting, which worked out pretty well, and didn't involve a lot of effort.

It was an interesting experiment, and one I'm happy to say was a reasonable success. I still have one issue involving duplicate chunks being recieved, which doesn't cause any harm other than wasting some bandwidth. I think it has to do with requests timing out on the client before the server has had a chance to send it. Nothing major, but something I'll no doubt make sure gets cleared up before our next game ships. :)