Having problems myself, php-nuke was installed and working fine, then of course I made the fatal mistake of changing the template in the admin and now nothing works.
Here is the error messages I get...checked for the Header.php file, it is installed.
Code:
Warning: head(themes/Pack-subBlack3dblue/theme.php): failed to open stream: No such file or directory in /home/sdhansen/public_html/EoD2/header.php on line 31
Warning: head(): Failed opening 'themes/Pack-subBlack3dblue/theme.php' for inclusion (include_path='.:/usr/local/lib/php') in /home/sdhansen/public_html/EoD2/header.php on line 31
Fatal error: Call to undefined function: themeheader() in /home/sdhansen/public_html/EoD2/header.php on line 47
Any help would be appreciated.