安装插件：

compile ":ckeditor:4.5.4.0"

在config.groovy中增加如下内容：

ckeditor {config = "/js/myckconfig.js"skipAllowedItemsCheck = falsedefaultFileBrowser = "ofm"upload {basedir = "/uploads/"overwrite = falselink {browser = falseupload = trueallowed = []denied = ['html', 'htm', 'php', 'php2', 'php3', 'php4', 'php5','phtml', 'pwml', 'inc', 'asp', 'aspx', 'ascx', 'jsp','cfm', 'cfc', 'pl', 'bat', 'exe', 'com', 'dll', 'vbs', 'js', 'reg','cgi', 'htaccess', 'asis', 'sh', 'shtml', 'shtm', 'phtm']}p_w_picpath {browser = trueupload = trueallowed = ['jpg', 'gif', 'jpeg', 'png']denied = []}flash {browser = falseupload = trueallowed = ['swf']denied = []}}
}

复制下面的内容，保存到/web-app/js，命名为：myckconfig.js

/*** @license Copyright (c) 2003-2013, CKSource - Frederico Knabben. All rights reserved.* For licensing, see LICENSE.html or http://ckeditor.com/license*/CKEDITOR.editorConfig = function( config ) {// Define changes to default configuration here.// For complete reference see:// http://docs.ckeditor.com/#!/api/CKEDITOR.config// The toolbar groups arrangement, optimized for two toolbar rows.config.toolbarGroups = [{ name: 'basicstyles', groups: [ 'basicstyles', 'cleanup' ] },{ name: 'paragraph',   groups: [ 'list', 'indent', 'blocks', 'align', 'bidi' ] },{ name: 'insert' },{ name: 'links' },{ name: 'styles' },{ name: 'colors' },{ name: 'about' }];// Remove some buttons provided by the standard plugins, which are// not needed in the Standard(s) toolbar.config.removeButtons = 'Underline,Subscript,Superscript';// Set the most common block elements.config.format_tags = 'p;h1;h2;h3;pre';// Simplify the dialog windows.config.removeDialogTabs = 'p_w_picpath:advanced;link:advanced';
};

在_form.gsp中，需要用的地方，改成这样

<ckeditor:resources/>
<div class="fieldcontain ${hasErrors(bean: news, field: 'content', 'error')} "><span class="property-label"><g:message code="news.content.label" default="Content"/></span><span class="property-value"><ckeditor:editor name="content" width="95%">${news?.content}</ckeditor:editor></span>
</div>

附件是改好的main.css，下载后将后缀.zip去掉即可