Er, I got a bit distracted by a riff or two when watching the riff, so I went back and made an alternate cover. If you've heard the riff, you'll understand why the photos have changed. the front's the same, but here's the altered back cover: (Spoilered since it refers to some jokes in the riff.)
a download for the full version.
And this, well, needs no explanation: (but I'll give it a spoiler, since it has a riff in it.)