You'll find descriptons of window elements below.
Commands - all available commands are displayed in this list.
Current Keys - all currently key shortcuts assigned to the selected command are displayed in this list. You can remove a shortcut using the Remove button.
Select New Shortcut Key - after selecting a command, click in this field and press key combinatinon that you'd like to assign. After it's displayed in this field. use the Assign button to assign it.
Use the Reset All button to restore default shortcuts for all available commands.
See also