I loved most of this game, i loved how many solutions there were to the levels, the graphics and sound were top notch.
The only reason i didnt finish it that retrying levels took a long time. Later levels require multiple perfectly-positioned items, and every reset you have to re-place every item, which takes a long time. I'd usually know the solution to a puzzle long before i actually solved it, leading to me spending quite a while in that miserable stage of knowing how to solve a puzzle but being stuck with the buzywork of actually doing so.
Somebody said this reminded them of polybridge, so imagine this: what if polybridge deleted your bridge every time it collapsed and you had to rebuild it from scratch? That is - in effect - what your game does. You've got a lot of room to expand these mechanics, but not if you keep knocking down my bridge.