I've spent the past few hours looking through the help and discussions and if I've found the answer to my question, I wouldn't know it.

I am trying to hard code the AutoNav block to show all of the top level pages and the sub pages below that - and if a sub page has a page below that it will slide out to the right.

Here is an example of what I am trying to do:http://www.antropy.co.uk/
Under the 'Services' menu, there are several sub pages and two of them have pages below that that slide out to the right when you mouse over.

Here is what I have and it only shows the first level of pages. I have made several changes but nothing seems to cause the menus to slide out to the right.
<?php
$bt = BlockType::getByHandle('autonav');
$bt->controller->displayPages = 'top';
$bt->controller->orderBy = 'display_asc';
$bt->controller->displaySubPages = 'all';
$bt->controller->displaySubPageLevels = 'custom';
$bt->controller->displaySubPageLevelsNum = '1';
$bt->render('templates/main_menu');
?>

Thanks for you help!