Ingo, tx for replying

The series are DataObjects, i will post my code below.

The meaning of it all....I stream videos on an Internal Network ( among other stuff i present on the webpage ), so i provide a webpage for people to look trough the series and pick a episode to watch. Everybody loves the way it works ( tx SilverStripe guys ).
Offcourse i could stay with 2.3.7. but i want to move on.....

-----------------Code Video--------------------------

class Video extends DataObject {
   
    static $db = array(
'Name' => 'Varchar',
    'Server' => 'VarChar',
    'Folder' => 'VarChar',
    'Omschrijving' => 'Text',
    'URLSegment' => 'Varchar(255)');

   static $has_one = array(
      'VideoPage' => 'VideoPage',
      'Photo' => 'Image');   
   
    static $has_many = array(
            'VideoCats' => 'VideoCat',
            'VideoStreams' => 'VideoStream');
   
   public function getCMSFields(){
    return new FieldSet(
       new TextField('Name'),
         new TextField('Server'),
         new TextField('Folder'),
         new TextareaField('Omschrijving'),
         new ImageField('Photo', 'COVER'),
         
            new DataObjectManager(
               $this,
               'VideoCats',
               'VideoCat',
               array('Name' => 'Naam', )));
         }
   
   public function getThumb(){
      if($this->PhotoID)
         return $this->Photo()->CMSThumbnail();
      else
         return '(No Photo)';
   }   
   
   public function getLinkingMode(){
      if($this->URLSegment == Director::URLParam('Action')){
         return 'current';
      }
      else{
         return 'link';
      }
   }

public function onBeforeWrite(){

if($this->Name){

$this->URLSegment = SiteTree::GenerateURLSegment($this->Name);

if($object = DataObject::get_one($this->ClassName, "URLSegment='".$this->URLSegment."' AND ID !=".$this->ID)){

$this->URLSegment = $this->URLSegment.'-'.$this->ID;

}

} else {

$this->URLSegment = SiteTree::GenerateURLSegment($this->ClassName.'-'.$this->ID);

}

parent::onBeforeWrite();

}
}
---------------------- end of code Video ------------------

---------------------- code VideoCat ----------------------

class VideoCat extends DataObject {

   static $db = array('Name' => 'Varchar');

   static $has_one = array('Video' => 'Video');

   static $has_many = array('VideoStreams' => 'VideoStream');

function getCMSFields() {
   return new FieldSet(
         new TextField('Name', 'Categorie '),
         new DataObjectManager(
                               $this,
                               'VideoStreams',
                               'VideoStream',
                               array('Name'=>'Naam')));
}

}

------------------- end of code VideoCat ---------------------------

------------------- code VideoStream --------------------------------

class VideoStream extends DataObject {

   static $db = array('Name' => 'Varchar');

static $has_one = array(
   'Video'=> 'Video',
'VideoCat' => 'VideoCat');

function getCMSFields() {
   return new FieldSet(
         new TextField('Name', 'exacte naam van het file, ZONDER extensie'));
}
}

--------------- end of Code VideoStream --------------------------------

--------------- Code VideoPage -----------------------------------------

class VideoPage extends Page {
   
static $has_many = array('Videos' => 'Video');
   
function getCMSFields() {
   $fields = parent::getCMSFields();

   $dataobjectmanager = new HasManyDataObjectManager(
      $this,
      'Videos',
      'Video',
      array('Thumb' => 'Photo', 'Name' => 'Name','Server' => 'Server', 'Folder' => 'Folder', 'Omschrijving' => 'Omschrijving'),
      'getCMSFields_forPopup'
   );
   $dataobjectmanager->setPluralTitle("een video");
   $fields->addFieldToTab("Root.Content.Video", $dataobjectmanager);
   $fields->removeFieldFromTab("Root.Content.Main","Content");
   return $fields;
}

class VideoPage_Controller extends Page_Controller {
   
function init(){
parent::init();
Requirements::JavaScript('/mysite/javascript/jquery.min.js');
Requirements::JavaScript('/mysite/javascript/prototype.js');
}

   
   public function getIndividualVideo(){
      
      if($URLAction = Director::URLParam('Action')){

         $VideoID = Convert::raw2xml($URLAction);
      
         if($VideoID ){
            return DataObject::get_one('Video', "URLSegment='".$VideoID."'");
         }
      }
   }
}
---------------------- end of Code VideoPage --------------------------

Tx, but no... i don't use the Director::addRules() command as far as i know. At least i didn't put it anywhere.... But doesn't my Public function 'getindividualVideo' takes care at providing the link.?

ps: You can tell i'm a total beginner at this right? ;)