There is a small square that is visible when pan mode is off. The arrow keys, when pressed, move the board around when pan mode is on, otherwise they move a small square around.
The space bar, when pressed, calculates the next generation when pan mode is on. The cell under the small square, changes to the current color when pan mode is off and the space bar is pressed.
The rule table entries, when click on, flip their values, when xor mode is on. They change to the current color when xor mode is off. The values they flip to, when xor mode is on, depends on the current color and sometimes they don't flip their values. 1