To fix the issue with client hanging try this:

1) Alt Tab to another program (I use Chrome)
2) Click on that window to ensure it's active and your system is responsive.
3) Alt Tab back directly to the editor (NOT the stats editor)
4) Alt Tab back to the editor
5) Press Alt on your keyboard and check that the menu in the top left is highlighted.
6) Click on a different cell in your opened stats editor document
7) Everything should work now.