Oh really? Which button did you use for jumping? Or was it to stick together to another box? Also if you click on the box to deselect it, it will select it again, so you have to click anywhere except on the active box to deselect it.
I used space And yes, I know how the selection in the game works, it was that more than half of the time the clicking just didn't work, when I had selected something and tried to click somewhere else, nothing happened (and after a few tries it worked)
Oh :( Sorry that happened, we'll probably have to redo the selection method in the future, since we wanna check if it's possible to change it towards controller input.