First resque the purple puffle,When you resqued the purple puffle,you will be redirected to the ice falls. After.enter the room hidden.
When you enter it,it will come like this.
Go in the vent as in this picture.
Then go though the pipes to the other end.
Walk up to the machine as in the picture.
Then,all puffles will be to normal then claim your 5000 coins and your free gift! Hope this helped.