magento - How to send email with a custom email template -

i creating template abandoned orders. when try use template created, send blank email, more template appears in: system/transactional email

template

the temaplate copy of order_update.html name test_order_update.html in en_us/template/email/sales/

config.xml - working

<global>         <template>         <email>             <custom_template  module="mymodule">                 <label>abandoned transactions</label>                 <file>sales/test_order_update.html</file>                 <type>html</type>             </custom_template>         </email>     </template> </global> 

shooting - not load template

<?php     $storeid = mage::app()->getstore()->getid();      $emailtemplate = mage::getmodel('core/email_template');     $emailtemplate->loaddefault('test_order_update');     $emailtemplate->settemplatesubject('my subject here');      $email = mage::getstoreconfig('trans_email/ident_sales/email');     $name = mage::getstoreconfig('trans_email/ident_sales/name');      $emailtemplate->setsendername($name, $storeid);     $emailtemplate->setsenderemail($email, $storeid);      $emailtemplatevariables['username']  = ' something';     $emailtemplatevariables['store_url'] = mage::getbaseurl(mage_core_model_store::url_type_web);      $emailtemplate->send('myemail@gmail.com', 'name...', $emailtemplatevariables); ?> 

email received

sender: sales <sales@example.com> subject: subject here content:  

try replacing

$emailtemplate->loaddefault('test_order_update'); 

with

$emailtemplate->loaddefault('custom_template'); 

because load email template have give tag name provide in config.xml

also add following line before sending mail

$emailtemplate->getprocessedtemplate($emailtemplatevariables); 

if template copy of order_update.html need pass order object teh email parameter.