There are two ways of exiting presentation mode, you can press either ESC key or click with the quit button that appears when placing the mouse in the top-right corner. Of course you can cycle windows (Alt+TAB by default)
Hai dous xeitos de saír do modo de presentación: pode premer a tecla ESC ou premer o botón de saír que aparece cando se pon o rato na esquina superior dereita. Aínda pode circular polas fiestras (Alt+TAB por omisión) Reason for inhibiting the screensaver activation, when the presentation mode is active