I followed Brians small tutorial.
Got the same problem as u, found out that the "Custom" layout did not work so i just put "Default" as layout, could then after change to custom layout.
in the contents_update.php - file i just renamed the path to "../HTMLEditor/" and added the <?php require_once("../HTMLEditor/WARichEditorPHP.php"); ?> in the grp of requiers at the top of the page. Removed all the old paths to iRight.
With the contents_insert.php - file
I followed the tut and insterted a new editor, change the team from "Custom" to "Default", cos after it was just blank and gave a error that said it could not find "Custom".
Made the proper changes in the code to match the old iRight.
Hope this helps you out m8