Instance picking -- where am I going wrong here?

Hi all - apologies if this is vague; I have a bunch of red squares that are in a family called map_items - these are pinned to a larger purple square so that they can all move around together. When you click on a red square a boolean variable is toggled - and if on, the square changes to green. Now what is meant to happen is if the variable is on that square is to be positioned over another target square - and since everything is pinned together the purple square and surrounding squares move around with it. Now if you look at my example you will see 4 red squares pinned to a purple square, if you click the top left one it works perfectly. But if you (reset the .capx) click any of the other ones, they will toggle on however they won't set their position to the target square like the top left red square does. Can anyone explain what is going wrong in my events? Thanks very much

capx here: https://www.dropbox.com/s/mm04jbpyg8tq4nv/help.capx?dl=0

Try this:

For a different thing but the logic should apply here.

Thanks for your help, that certainly helped me verify that I was picking the correct instance and it's highlighted a deeper problem with what I'm trying to do - seems multiple objects pinned to one and other can't be moved in the way I need to move them. Thanks again.