Actually it's very hard to do that thing that you ask; you need a crapton of thyme. You can do this: when you want everything to hold its place, you make the boxes weigth +inf
So when it's moveable:
density = 0.6 (Why do you use so little? You should use 100 for this)
When you click and want everything to be glued:
density=+inf
You need an infinite force to move an object with +inf density, so it won't move
The idea i told you is rather easy: first of all press F10 and the CONSOLE will pop up. There, write "scene.my.fix=100" (you can put any name, not just fix). Then you go to the box that you click to start (the one with timeToLive = 0 on onClick) and write this:
onClick = (e)=>{timeToLive = 0; scene.my.fix = +inf}
And you select all the boxes that you want to be static when you press the button, and you go to their script meny, and find density. Write this there
density = {scene.my.fix}
Now, you'll want to make the boxes moveable once you win or whatever. You can just put a button that says "Try again" or something and put on it's onClick:
(e)=>{scene.my.fix = 100}
Or you can put that exact same code on the onCollide of a box at the end of the path
HOORAY!!!!!!!!! that is my thing done! i am litterally VERRRRRRRYYYYYYYY HHHHHAAAAAAPPPPPPPPPPPPPPYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYYEEEEEEEEEEEEEEEEEEEP
and also, i need the retry to reset the blocks back to where they started in the first place. (and the ball and also reset the click here to start block too )