Hmm, I played Lemmings and ONML far too few. :sad: I'd have to look it up, and that's most likely not the intension of this game.
So, just some wild guesses: 'Five alive' could be one, 'Lemming Hotel' had a strange skill distribution with every skill available IIRC, and then there was some long and boring snow level with five of each skill, but I don't remember its name/position.
EDIT: Just looked it up, it's Crazy 9, 'On the Antarctic Coast'.
EDIT2: More looking up, I was wrong with the first one, and right with my second guess. Hmm...
I doubt that this is enough to consider the question answered correctly...