Figured out how to lock up the game every time. If I select sort on the right border set of icons and then click on an icon, it seems to work but since I didn't complete the "sort" so it just locks up tighter than a tick.
Similarly with the bottom set of icons
Imho, all the icons should be disabled while "sort" is enabled and if you single click on them, they should just return a message "finish sorting" or some such.