The idea was for there to be two "good endings" -- one where you reverse the melt, and another where you learn to adapt. One had to be cut though. The oil ending was conceived more as a gag.
I did actually get a penguin model waiving in Blender. Thing is, that was my first-ever Blender animation, and the model broke trying to "work." Truth be told, I'm feeling lucky to have gotten textured penguins at all. One The strangest thing I learned while working on this game is that real penguins do in-fact have knees. They're inside their bodies, but they have them.