You can just tarball the files up and then put them on a thumb drive, or drag the file from the VM to your desktop (or wherever) if your software supports it. That said, I'm not sure offhand if Armory will run on 12.04. I remember there being some trickiness necessary in order to make Armory work on 12.04. That code is gone now. (Maybe there's another workaround I don't know about?) I'm inclined to say that usage of Armory 12.04 is a "caveat emptor" kinda deal, since it's no longer supported, but that's goatpig's call.