This is a simple guide to help get those 4 achievements from the new level Forest.
How to Obtain All Forest Achievements
For this one all you need to do is move a wagon to the cliff face with the stairs then walk up to the fire, grab a marshmallow and put it on the fire.
This one is probably the easiest to get. All you need to do is pull the crane boulder to the left.
On Thin Ice
For this one you need to grab the piece of wood sitting next to the fence and place it on top of the ice cube. Then take the cube up the hill without letting it melt...
You obviously cant miss this one but all well its on here too.