Have to pick spider that goes with the box. 1 way to do this is use containers. But that means also that you have to create spider & box during runtime.
Another way is to just give spider & box a identification number (or string). Those with the same identification number are a pair.
Like this:
https://www.dropbox.com/s/wod7r8c939bta ... .capx?dl=0
I gave spider & box an instance variable 'ID'. In the layout editor i gave them matching numbers.
Now, if you pick one, you also pick the other.
As in event 3, where i pick each box, and at the same time the spider with the same ID as the box. Now the right spider gets set to the position of the right box.
As in event 20. Where the 'on collision' auto picks a box. And i pick the spider with the same ID. The action of the box is updated, and the mirroring of the spider with the same ID is updated.