How to kill the BouncingAtomsMorph window in Pharo By Example

Right-click the window
left-click the box at the left-hand end of the 'Select'/'deselect' option's row
   - this brings up the 'Morphic halo' or clickable buttons to do with sub-window management
left-click the window-close Morphic button - the X at the top-left of the window

The halo *should* appear if you meta-click (i.e. middle-click) the window - but it doesn't on my Windows install of the PBE-OneClick zip (which is id-ed as Pharo-1.0 Latest update: #10517 in System | About )

The BouncingAtomsMorph window - with and without the Morphic halo