the problem it looks like is in your include_once("fckeditor.php"); ..... that needs to be referenced correctly from where your page is to that file. It also says at the bottom that your BasePath attribute for the editor is '/fckeditor/' that means that from the root directory the folder "fckeditor" is there. if this is not the case, you will want to change that, and then the top include_once("fckeditor.php"); will be the same, as your basepath, but you just give it the path to fckeditor.php appended to the end.
Re: fck integrate problem
Hope that helps,
~Sokol