How do I add tabledrag with 'weight' to admin form

I have built a fairly basic module but i'm struggling with the UX of the admin form. Essentially I need a list of items that have several values; a textfield, checkbox, select list and a button to delete them.

I've built all of the functionality (including the "add one more" using the example in the drupal ajax examples module) and its working great, except now I need to be able to reorder the items and the webmin style up/down buttons are not good UX. I've been hacking to no avail at numerous examples like:http://www.urbaninsight.com/2012/09/11/creating-table-with-draggable-weights-in-drupal-7

It doesn't appear that theme_hook_form is being called so I can't inject the weight javascript, styles or markup.

I added this to the .module file:

function module_cache_theme() {  dpm("themehook");  return array('theme_module_settings_form' => array('file' => 'module_form.inc','arguments' => array('form' => NULL),    ),  );}

The menu item is in the hook_menu:

  $items['admin/config/development/module'] = array('title' => 'module','description' =>'','page callback' => 'drupal_get_form','page arguments' => array('module_settings_form'),'access arguments' => array('administer site configuration'),'file' => 'module_form.inc',  );

When the cache is regenerated I get a dpm message but the method theme_module_settings_form is never being triggered.

Ideas?