Very nice puzzle game!
I might miss something in the tutorial, but I would make it easier to remove objects, for example with the right click over them. It becomes a little tedious if you just misplaced something after placing other elements and you need to reset the whole level.
I'd tell players that sometimes they won't need all the items that a level gives you, if that is a conscious choice. That's a completely different topic, anyway.
The idea is great, I like that text rhymes, I think it deserves a full version!