Are you talking about my example? If so then it will only work if you hold left mouse button down over an object that exists. i.e: the airplane. The reason for this is so that it only executes the command or item from inventory on the object below the cursor.
However there are multiple ways to go about creating this sort of interface. Mine is just one of many.
I believe this
page here, might be of interest to you. Although it seems I have yet to create the tutorial page for the coin/ring interface. Oh well...