You don't have to quit the game via Alt+F4 or Cmd+Q any longer. If you really want to pause from this excellent game, you just can hit "Quit" in the settings menu ;-) Your progress will be saved.
In addition, the cursor was modified, fixing problems when scrolling in your inventory or spell list.
Still working on improving the keyboard commands - but this will take some time...
We have a Quit Game Button!
Source: Steam Community (opens in a new tab)