Customize Email Body Content + Mandrill template

Customize Email Body Content + Mandrill template

I have followed this article:
http://blog.mandrill.com/own-your-wordpress-email-with-mandrill.html
But the author is talking about dynamic regions only. I want to use merge
tags. I want to customize the body content using user personal details
which has been extended using Cimy User Extra Fields.
Please help.
Update:
Clearer explanation:
I've followed the article mentioned above and all is well. But the author
suggest to customize the body content using dynamic region.
Note: You can customize Mandrill template using 1) dynamic regions, 2)
merge tags. Below is example for dynamic regions :
$message['template']['content'][] = array(
'name' => 'user_name',
'content' => 'Name'
);
$message['template']['content'][] = array(
'name' => 'password',
'content' => 'Password'
);
$message['template']['content'][] = array(
'name' => 'mobile_site',
'content' => 'http://m.com.com'
);
OK. Let's forget the merge tags. I'm ready to use dynamic region as per
example above. So how do I populate the 'content' key with user data?
(This is a template for new user registration key). Moreover, how do I
populate user data which are extended by the plugin "Cimy User Extra
Fields"?