Based on the screenshots I think I've been everywhere in the game, but I have the sense I haven't seen all it has to offer so I love that! Precisely after writing that, having been playing for around 20 minutes, I found the purple baby... So that may be it, right?
I did experience some visual glitches, but I am playing on Linux through Wine so that may be it...
Really nice demo! Clearly lots of work went into it.