just a note for level 71. if you get stuck cause some of you pieces pop into place under another, you can still beat it if they are one on top of the other.
i also really dislike the fact that the tacks and glue wear out if you dont use all of them by the end of the round. kind of wasteful. 4/5 because other than that and the other things already mentioned (i hate repetitive posings) it is way better than the other btd games i have played.