Custom node with image cck field giving me grief! (noobzer here!)

O.K., so I'm creating a module that creates a new node type. I followed the node_example in the Drupal API tutorials and everything is well and good: I can create a node with various text fields and checkboxes, no problem. The problem? Now I want to add an image field to my node. Still no big problem, except that when I call content_field_instance() on my image field, suddenly all my other fields (the text fields and checkboxes I had defined before) appear twice (including the title)!

Any idea what's going on?

Just to give you more info, here's how my node's hook_form() is structured:

function mycustomnode_form(&$node)
{
   /*
    * Set up the title and body
    */
    $type = node_get_types('type', $node);
    $title = array(
      '#type' => 'textfield',
      '#title' => check_plain($type->title_label),
      '#required' => TRUE,
      '#default_value' => $node->title,
      '#weight' => -20,
    );

    $body = node_body_field($node, $type->body_label, $type->min_word_count);
    $body['#weight'] = -15;
   
   /**
    * Include fields for this form
    */
    
    /*
     * The Picture/Image field.
     */
    /* First, get the image field settings:*/
    module_load_include('inc', 'mycustomnode', 'mycustomimage');
    $picturefield = mycustomimagefield();
   
    /* Now let CCK build/instantiate the image field on its own*/
    module_load_include('inc', 'content', 'includes/content.crud');
    content_field_instance_create($picturefield);
    
    
    
   /*
    * The Button Field
    */
    module_load_include('inc', 'mycustomnode', 'mybuttons');
    $buttonfield = mybuttonfield();
   
   /**
    * Terms and Conditions
    */
    module_load_include('inc', 'mycustomnode', 'conditions');
    $conditions = conditionsfield();

   
   
   /**
    * Now build the form
    */
    $form = array($title, $body, $buttonfield, $conditions);
   
    return $form;
}

where of course the files conditionsfield(), mybuttonfield(), and mycustomimagefield() are .inc files that simply define a field in the following style:

$buttonfield['buttonsfs'] = array(
      '#type' => 'fieldset',
      '#collapsible' => TRUE,
      '#title' => t('My Buttons'),
      '#description' => 'This field is just a bunch of checkboxes',
    );
    
    
   /*The enable checkboxes*/
   $buttonfield['buttonsfs']['coolbutton']['enable'] = array(
         '#type' => 'checkbox',
         '#title' => t('Cool Button'),   
    );
    $buttonfield['buttonsfs']['neatbutton']['enable'] = array(
         '#type' => 'checkbox',
         '#title' => t('Neat Button'),
    );
    $buttonfield['buttonsfs']['awesomebutton']['enable'] = array(
         '#type' => 'checkbox',
         '#title' => t('Awesome Button'),
    );
    

So basically the node form all looks great if I disable the image field (i.e. if I comment out the line that calls content_field_instance), but if I call content_field_instance to insert the image field, all my other fields get displayed twice??

Any ideas? Thanks!