XnViewWiki:
If you have set the transition to "Use Keyboard Press our Mouse click", you can navigate using the mouse buttons or the keyboard. The right mouse button displays the next picture, the left mouse button displays then previous. The arrows keys can also be used to navigate through the slide show.
no matter which button I press the slide show always shows only the next picture
slide show navigation
Moderators: XnTriq, helmut, xnview