Here's my theory without having looked into the code: Basically, your original filenames contain funky characters that the Artchive robot doesn't like. Specifically, your files have a tilde (~) in them, presumedly to truncate them for longer filenames (are you using Windows? it's okay, you can admit it). We haven't tweaked our system to reject those files outright, or accept them gracefully. In the meantime, please make sure all of your upload files have original names composed solely of alphanumeric characters.
Also, congrats Steven for being one of the most prolific SITO/Artchivists of all time!