You mean the commands on the LCD display when you are in an activity? Go to customize the activity and there is an option to change the behavior of buttons. At the bottom of this page you define what is on the LCD screen. There doesn't seem to be a nice way to re-order the buttons, I had to manually change each one. On the 520 the commands listed in the setup are displayed left to right, top to bottom. There doesn't appear to be a way to leave a button blank on one page either, but if you wanted to you may be able to give it a command with no label (didn't actually try.)