Multipage User Registration Forms based on Role

I am developing a module for supporting multipage user registration forms based on role. It is an entire application process that is going to take people several hours to complete and in the end will support saving progress via session and cookies, and maybe even a temp account or code. Right now I am beginning and got a multipage form with all the required fields set up etc. I however am having a problem.

The application/registration gets to page 2 and when I hit next it doesn't ever run my multipage_registration_form_alter function instead stopping progress when it doesn't see name and email in form_state. I can put it in manually in multipage_form_user however it then creates the user and altho it shows the next page... it is then editing instead of applying.

My question is why is it not getting to my code after page two, to even respect form_state['rebuild'] being set to true and why is it running the code 2x on page 2. Debug output and module code below.
Initial Load:

Page 1 of 8
Array ( [storage] => Array ( [page] => 1 [values] => Array ( [0] => ) ) [submitted] => [post] => Array ( ) [rebuild] => 1 [#validate] => Array ( [0] => multipage_registration_user_register_validate ) ) 

First click of "Next >":

Page 1 of 8<br>Array
(
    [storage] => Array
        (
            [page] => 1
            [values] => Array
                (
                    [0] => 
                )

        )

    [submitted] => 
    [post] => Array
        (
            [name] => test
            [mail] => test@test.com
            [profile_last_name] => Testlast
            [profile_first_name] => Testfirst
            [profile_gender] => Male
            [profile_middle_initial] => T
            [timezone] => -21600
            [form_build_id] => form-fe40e26af8a7e7821b404c55b026737e
            [form_id] => user_register
            [op] => Next >
        )

    [rebuild] => 1
    [#validate] => Array
        (
            [0] => multipage_registration_user_register_validate
        )

)
Page 2 of 8<br>Array
(
    [storage] => Array
        (
            [page] => 2
            [values] => Array
                (
                    [0] => 
                    [1] => Array
                        (
                            [name] => test
                            [mail] => test@test.com
                            [profile_last_name] => Testlast
                            [profile_first_name] => Testfirst
                            [profile_gender] => Male
                            [profile_middle_initial] => T
                            [timezone] => -21600
                            [op] => Next >
                            [submit] => Next >
                            [form_build_id] => form-b79377fd1faef029c0e2dcedbf82ad7b
                            [form_id] => user_register
                        )

                )

        )

    [submitted] => 1
    [rebuild] => 1
    [#validate] => Array
        (
            [0] => multipage_registration_user_register_validate
        )

    [values] => Array
        (
            [name] => test
            [mail] => test@test.com
            [profile_last_name] => Testlast
            [profile_first_name] => Testfirst
            [profile_gender] => Male
            [profile_middle_initial] => T
            [timezone] => -21600
            [op] => Next >
            [submit] => Next >
            [form_build_id] => form-b79377fd1faef029c0e2dcedbf82ad7b
            [form_id] => user_register
        )

    [clicked_button] => Array
        (
            [#type] => submit
            [#value] => Next >
            [#weight] => 30
            [#id] => next
            [#post] => Array
                (
                    [name] => test
                    [mail] => test@test.com
                    [profile_last_name] => Testlast
                    [profile_first_name] => Testfirst
                    [profile_gender] => Male
                    [profile_middle_initial] => T
                    [timezone] => -21600
                    [form_build_id] => form-fe40e26af8a7e7821b404c55b026737e
                    [form_id] => user_register
                    [op] => Next >
                )

            [#programmed] => 
            [#tree] => 
            [#parents] => Array
                (
                    [0] => submit
                )

            [#array_parents] => Array
                (
                    [0] => submit
                )

            [#processed] => 
            [#description] => 
            [#attributes] => Array
                (
                )

            [#required] => 
            [#input] => 1
            [#name] => op
            [#button_type] => submit
            [#executes_submit_callback] => 1
            [#process] => Array
                (
                    [0] => form_expand_ahah
                )

        )

)

Third click of "Next >":
No output as it never gets to the debugging statements in multipage_registration_form_alter

However it does say:

* You must enter a username.
* You must enter an e-mail address.

Code below:

<?php 
// $Id$
function multipage_registration_form_alter($form, $form_state, $form_id){
     switch($form_id){
          case 'user_register':
               $showcats = array(
                         2,
                         2,
                         2,
                         1,
                         1,
                         1,
                         1,
                         3
                    );
               $page = null;
               if($form_state['submitted'] == 1 && $form_state['clicked_button']['#id'] == 'next'){
                    $form_state['storage']['page']++;
               }
               $lastpage = count($showcats);
               if(isset($form_state['storage']['page'])) {
                    $page = $form_state['storage']['page'];
                    if(!isset($form['values']['name'])) $form['values']['name'] = $form_state['storage']['values']['name'];
                    if(!isset($form['values']['mail'])) $form['values']['mail'] = $form_state['storage']['values']['mail'];

               } else {
                    $page = $form_state['storage']['page'] = 1; 
               }
               echo "Page $page of $lastpage<br>";
               $form_state['storage']['values'][$page - 1] = $form_state['values'];
               #print_r("values: ".$form_state['values']);
               if($form_state['clicked_button']['#id'] == 'prev'){
                    $page = $page - 1;
                    echo "prev set<br>";
                    unset($form_state['values']['prev']);
               }
               $countstart = 0;
               $countend = 0;
               for($i=0;$i<$page;$i++){
                    $countstart += $showcats[$i];
                    $countend += $showcats[$i];
               }
               $countstart -= $showcats[$i - 1];
               $categories = _profile_category_weight_categories();
               $count = 0;
               foreach($categories as $formkey=>$weight){
                    if($count >= $countend || $count < $countstart){
                         unset($form[$formkey]);
                    }
                    $count++;
               }
               $form['submit']['#value'] = t('Next >');
               $form['submit']['#id'] = 'next';
               if($page > 1){
                    $form['prev'] = array (
                              '#type'=>'submit',
                              '#value'=>'< Prev',
                              '#id'=>'prev'
                         );
               }
               if($page == $lastpage){
                    $form['submit']['#value'] = t('Complete');
               }
               else $form_state['rebuild'] = TRUE;
               $form_state['rebuild'] = TRUE;
               $form_state['#validate'] = array('multipage_registration_user_register_validate'); #never gets to this stage
               print_r($form_state);
               break;
     }
}
function multipage_registration_user($type, &$edit, &$user, $category = NULL){
     /*
     echo "Type: ";
     print_r($type);
     echo "<br>Edit: ";
     print_r($edit);
     echo "<br>User: ";
     print_r($user);
     echo "<br>Category: ";
     print_r($category);*/
}
function multipage_registration_user_register_submit($form, &$form_state){
     print_r("submit: ".$form);
     if(isset($form_state)){
     }
}
function multipage_registration_user_register_validate($form,&$form_state){
     echo "validate: <br>";
     print_r($form_state);
     if(isset($form_state)){
     }
}

function multipage_registration_help($path,$arg){
     $output = '';
     switch($path){
     default:
          $output = '<p>' . t("Help for multipage registraton") . '</p>';
     }
}

function multipage_registration_perm(){
     return array('access multipage_registration','administer multipage_regristration');
}