When smf 2.0's publish.
Menus codes has moved to Sources folder.
I'm gonna tell you "how add button to theme".

Open Subs.php and find:
$buttons = array(
'home' => array(
'title' => $txt['home'],
'href' => $scripturl,
'show' => true,
'sub_buttons' => array(
),
),
Add after:
'SMFGrup' => array(
'title' => 'SMFGrup Alemin En Baba Destek Sitesi',
'href' => 'http://www.smfgrup.com',
'show' => true,
'sub_buttons' => array(
),
),Change areas yourself.

friends thanks