Panel is the name of the panel.
RowLength is the maximum number of buttons in a row (counting from left to right). You can specify a number or the word SingleRow.
Margin is the amount of white space, in pixels, between buttons.
ButtonWidth is the width of each button. This argument is optional.
ButtonHeight is the height of each button. This argument is optional.
Off is the word off.
This makes the panel stop rearranging itself.
Once you use this command for a particular panel, that panel will keep arranging itself automatically every time you add or remove a button.
If you omit ButtonWidth and ButtonHeight, the program doesn't change the sizes of buttons.