Our PHP Plugin is a little bit dated. I know, but PHP has not a stable API which makes it impossible to have one plugin for all versions.
So to get the PHP plugin to run, you nee the right library. So download PHP library for Mac and Linux from our website: macsw.de/plugin/PHP/. Download the windows installer here: museum.php.net/php5/php-5.2.3-win32-installer.msi.
If you compile our example projects, please change the file path. "C:\Programme\PHP\php5ts.dll" won't work for an english system.