Add wysiwyg editor successfully with image insert for magento 1.5.2

Question

1) open file Block_Adminhtml__Edit_Tab_Form

edit field

$form = new Varien_Data_Form();
  $this->setForm($form);
  $fieldset = $form->addFieldset('developerpage_form', array('legend'=>Mage::helper('developerpage')->__('Item information')));

/* add below code here */

  $configSettings = Mage::getSingleton('cms/wysiwyg_config')->getConfig();
  $configSettings['files_browser_window_url'] = $this->getBaseUrl().'admin/cms_wysiwyg_images/index/';
  Mage::getSingleton('cms/wysiwyg_config')->setConfig($configSettings);

/* for fieldset add like below */

$fieldset->addField('detail', 'editor', array(
          'name'      => 'detail',
          'label'     => Mage::helper('developerpage')->__('Content'),
          'title'     => Mage::helper('developerpage')->__('Content'),
           'style'     => 'width:700px; height:500px;',
          'config'    => $configSettings,
          'required'  => true,

      ));

2) open controllers/adminhtml/testcustomercontroller.php find editAction

in editAction find $this->loadLayout(); and paste the below code;

$this->getLayout()->getBlock('head')->setCanLoadExtJs(true);
        if (Mage::getSingleton('cms/wysiwyg_config')->isEnabled()) {
            $this->getLayout()->getBlock('head')->setCanLoadTinyMce(true);
        }

3) open desing/adminhtml/default/default/yourmodule xml file and add below xml

 /* this is my module change with yours */
<developerpage_adminhtml_developerpage_edit>
     <update handle="editor" />
 </developerpage_adminhtml_developerpage_edit>

NOTE: Dont give field name or id name  "content" of editor field nor in Database

Call  editor content like below other wise directive  would't convert 

$_cmsHelper = Mage::helper('cms');
$_process = $_cmsHelper->getBlockTemplateProcessor();
echo $_process->filter(Here your database content);

Now image can be insert. :)