Okay, okay, I'm really sorry about this as it looks like the Archiver is
proprietary. DO NOT DOWNLOAD IT!
Anyways, I think they may release the source code for the GUI if asked. After
all, if they've placed the object code under a BSD license, and released some
more of the program's source code, then they'll probably have no objection to
releasing the rest of it. Let's pester them at the links below until they do!
https://groups.google.com/forum/#!forum/b1-pack-discuss
https://github.com/b1-pack/b1-pack/issues
http://b1.org/support.jsp