You can't stack triangles, silly!
Got to 195.4m by building two towers and dumping triangles in between them. First the squares started shifting-squeezing eachother out. As though square is same weight as the rectangle, so its 2 times more dense.
I missclicked and put a triangle on one of the towers so continued with one.
Then the crane stopped giving me pieces.
Overall good prototype but needs spice.