Drupal render a button not working.

Hi, I want to make a table (with theme_table), and in each row reder 2 selects, and under the table, only one button for update all selects. All elements are render fine, but the button don’t working.

I read in some page add this lines:

unset($form_customer[‘actions’]);
$output .= drupal_render($form_customer[‘form_build_id’]);
$output .= drupal_render($form_customer[‘form_id’]);
$output .= drupal_render($form_customer[‘actions’]);
$output .= drupal_render($form_customer[‘form_token’]);
$output .= drupal_render($form_customer[‘options’][‘status’]);
//print drupal_render_children($form_customer);
$output .= drupal_render_children($form_customer);

And then render the button -> output .= drupal_render($form_customer[‘submit’]);
But don’t work :S Any idea??

Thx and sorry for my english,

Drupal version: 


Source: https://www.drupal.org/taxonomy/term/22/feed