A time ago i've met the issue that Yii doesn't run any client-side form validation when submitting the form by CHtml::ajaxSubmitButton. The small javascript below helps to fix it.
This tutorial will show you how to use the Pogostick Yii Extension Library to make an HTML TEXTAREA input element into a full-fledged WYSIWYG editor pretty much with very little code.
To start with you need to download the latest stable release of CKeditor.
Extract the downloaded file and place the ckeditor/ folder in your applications webroot directory. (beside "protected" and "css" and other directories)