THis smartdark theme which i so desperately am trying to get set up is causing me trauma. I have php-nuke 6.0, i know how to install themes but i keep getting an error message, do i need phpbb2? whatever that is lol.

Warning: head(themes/smartdark/theme.php): failed to open stream: No such file or directory in /home/horzman/public_html/home/header.php on line 31

Warning: head(): Failed opening 'themes/smartdark/theme.php' for inclusion (include_path='.:/usr/lib/php:/usr/local/lib/php') in /home/horzman/public_html/home/header.php on line 31

Fatal error: Call to undefined function: themeheader() in /home/horzman/public_html/home/header.php on line 47