Really nice concept. Platforming sections had me stressing, but I got there in the end. I like the star system too, had me redoing some levels to see if I could get all three. I missed a couple of frozen people in one of the levels, so maybe a speech bubble saying "help" or something like that would help the player identify them at the start.
Tons of levels too! You managed to squeeze a lot out of the melting/growing/wood mechanics.
Overall a great entry.