though modulecreator guys has added default field of "content" for editor:
$fieldset->addField('contentdesc', 'editor', array(
'name' => 'contentdesc',
'label' => Mage::helper('getthelooks')->__('Description'),
'title' => Mage::helper('getthelooks')->__('Description'),
'style' => 'width:500px; height:300px;',
'config' => Mage::getSingleton('cms/wysiwyg_config')->getConfig(),
'wysiwyg' => true,
'required' => true,
));
but even i change wysiwyg to true it didnt worked. module creator has forgot that to enable wysiwyg we also needed js for that
so here is complete simple layout xml file :
change getthelooks to your custom module name and enjoy!