-play: Start slide show automatically, in this mode closing full screen closes the viewer.
-dir [dir_name]: Load selected directory
-full: Start in Full Screen Preview mode
-pano: Start in Full Screen Panoramic mode.
-nav: Start in Full Screen Navigator mode.
-onlyfull: Will only permit full screen. Closing full screen will close the viewer.
-nosplash: Do not show initial splash screen on first run.
-ini [file_name]: Loads configuration from specified INI file (instead of user registry) and writes config back to the file in the end of execution.
Any other argument without "-" is added to file list as a file.