It's alright. The placement of the items sometimes has to be precise, can be tricky for that. The game play feels unpredictable when items start bumping into each other, but then I was probably trying something which is not the official solution
. In between the levels, always some tips are shown, which is annoying further in the game to see the basic tips over and over again and interrupting game play. The worlds have 12 levels, thus 36 stars max, so why is the progress in multiples of 18, that is weird. Too bad no leaderboards.