Not a lot I can say about this and to be honest the appearance of this video is a bit of a surprise.
Given it is out there now I've uploaded a version with audio onto my youtube account with a few notes :)
Here are some scenes from a playable prototype. It was something we built very rapidly and represents pre-pre-pre-pre (lots of pres) pre-Alpha quality. Even so it has a certain charm :)
What's the story behind it all? Like a lot of developers we work on a lot of different prototypes, they're just not usually shown in public. In this case an older version of the same video was leaked last week which came as a bit of a surprise if I'm honest. As it had no sound I thought there wouldn't be any harm sharing a version with audio.
Beyond that there's not a lot more I can say unfortunately :)