take and marge object

Hi againe, was thinking how can i marge, connect two object, example.
See picture… i place box nr 4 on the right place and the game know its ok but if i put in bad direction it will not work…if ther is simple way…and how i can wear object take and put one in other.
exemple.jpg

Lizard-13’s jigsaw puzzle example might help:

Actually, that was for GD4, so I have attached it converted for GD5, hoping that’s OK with him.
Puzzle.zip (42.9 KB)