Display warning messages in rules debug output

This is the rules output:
•0 ms "User account has been created" has been invoked.
•0.077 ms Executing the rule "Welcome Message" on rule set "User account has been created"
•0.192 ms Action execution: "Load a user account"
•6.383 ms Successfully added the new variable "load user"
•6.535 ms Action execution: "Send a message"
•6.669 ms Writing new message with subject welcome to trupal218 from admin
•8.725 ms Message not sent, reported error: Disallowed to send message because all recipients are blocked

Also, I use the LoginToboggan module so that users must validate their new user account via their personal email.
LoginToboggan module sets the user as non-authenticated role until they validate, then they are given the authenticated role.

I hope someone can shed light on solving this issue.

Regards

Below is the Rule trigger (http://drupal.org/node/327938#comment-2349964)

array (
  'rules' =>
  array (
    'rules_3' =>
    array (
      '#type' => 'rule',
      '#set' => 'event_user_insert',
      '#label' => 'Send Welcome Message',
      '#active' => 1,
      '#weight' => '0',
      '#categories' =>
      array (
      ),
      '#status' => 'custom',
      '#conditions' =>
      array (
      ),
      '#actions' =>
      array (
        1 =>
        array (
          '#type' => 'action',
          '#settings' =>
          array (
            'username' => '',
            'userid' => '1',
            '#argument map' =>
            array (
              'user_loaded' => 'user_loaded',
            ),
          ),
          '#name' => 'rules_action_load_user',
          '#info' =>
          array (
            'label' => 'Load a user account',
            'new variables' =>
            array (
              'user_loaded' =>
              array (
                'type' => 'user',
                'label' => 'Loaded user',
              ),
            ),
            'module' => 'User',
            'eval input' =>
            array (
              0 => 'userid',
              1 => 'username',
            ),
          ),
          '#weight' => -5,
        ),
        0 =>
        array (
          '#weight' => 0,
          '#info' =>
          array (
            'label' => 'Send a message',
            'arguments' =>
            array (
              'subject' =>
              array (
                'type' => 'string',
                'label' => 'Subject',
              ),
              'body' =>
              array (
                'type' => 'string',
                'label' => 'Body text',
                'long' => true,
              ),
              'recipient' =>
              array (
                'type' => 'user',
                'label' => 'Recipient',
              ),
              'author' =>
              array (
                'type' => 'user',
                'label' => 'Author',
              ),
            ),
            'module' => 'Privatemsg',
          ),
          '#name' => 'privatemsg_rules_new',
          '#settings' =>
          array (
            'subject' => 'Welcome',
            'body' => 'Welcome message test.',
            '#argument map' =>
            array (
              'recipient' => 'account',
              'author' => 'user_loaded',
            ),
          ),
          '#type' => 'action',
        ),
      ),
      '#version' => 6003,
    ),
  ),
)

With further investigating, I think this may have to do with the setting "Restrict Private Messaging to only related users" which I have set to "Allow sending messages only to confirmed relationships". I have this so that all users on my site cannot message each other unless they have a confirmed relationship, but my guess on what is happening is this setting also applies to Admin which is not allowing me to send this Welcome Message from the admin.

I opened this issue at http://drupal.org/node/678806 but keeping this issue open as I may be completely off on the reason for my issue.
Thank you

yea sorry, the 'rules setup2.png' above was suppose to be it but I made a mistake.
Please see the attached screengrab. The setup looks to be fine right? Hmm

Edit by Dave Reid: Added links to previously attached screenshots
http://drupal.org/files/issues/rules%20warning%20output.png
http://drupal.org/files/issues/permissions%20screenshot.png
http://drupal.org/files/issues/rules%20setup1.png
http://drupal.org/files/issues/user%20has%20roles.png
http://drupal.org/files/issues/user%20relationship%20privatemsg%20featur...

Hi Berdir,

(Good News! but starting with bad news..)

I create a clean install of drupal 6.15 with only the below two modules installed.
Privatemsg 6.x-2.x-dev 2010-Jan-07
Rules 6.x-1.x-dev 2009-Dec-11

I got the same error result with "Writing new message with subject Welcome! to xxx from ".
Screenshot attached.

I added line to privatemsg_rules.rules.inc as instructed.

function privatemsg_rules_new($subject, $body, $recipient, $author) {
  var_dump($author);
  rules_log(t('Writing new message with subject %subject to %user from %author', array('%subject' => $subject, '%user' => $recipient->name, '%author' => $author->name)));

Output:
array(4) { ["subject"]=> string(8) "Welcome!" ["body"]=> string(26) "Hey , welcome on our site!" ["#argument map"]=> array(2) { ["recipient"]=> string(7) "account" ["author"]=> string(10) "admin_user" } ["#eval input"]=> array(1) { ["rules_input_evaluator_php"]=> array(1) { ["body"]=> array(1) { [0]=> string(7) "account" } } } }

It looks like the "author" is just showing the machine readable variable name "admin_user".
Screenshot attached.

Now the Good News!
As you suggested I deleted the rule that comes with privatemsg and create the rule from scratch.
It looks the exact same as the rule that comes with privatemsg but it works! I wonder why..

Please let me know if I can do any additional testing to help fix the rule that comes with privatemsg.

Also, I still have an issue with "Allow sending messages only to confirmed relationships" feature of User Relationship module not allowing admin to send out emails.

Would you be able to assist for this in anyway?
http://drupal.org/node/678806#comment-2456948

This feature is really cool making users only able to send message to one another if they are friends.
But I think there should be a way to give exceptions for users such as admin.

Thank you

awesome, thanks!