Here's a simpler capx that isolates the issue..
Drag the brown object to the other blue object to pin it.. It displays correct UID, but it gets pinned to the incorrect object.
It appears as if it isn't taking into account the relation of the containers (sprite3 should be picked with the sprite2 that family1 collides with).
from the manual:
"If a condition picks one object in a container, every other associated object in its container is also picked."
But it's not pinning it to the picked object.