I have a "video" content type. I want to customize the template file for edit form,
page--node--add--video.tpl.php, but when I render (or print)
$form, it returns
What is the problem?
$form variable available in page.tpl.php (see the docs for a full list of available vars).
If you're trying to output the page content it's done like so:
<?php echo render($page['content']); ?>