add select column on manual join with Propel

    $c = new Criteria;
    $c->addJoin(InscritLignePeer::CAT, CategorieTarifPeer::CODE, Criteria::LEFT_JOIN);
    InscritLignePeer::addSelectColumns($c);
    $c->addSelectColumn(CategorieTarifPeer::LIBELLE);
    $c->addAscendingOrderByColumn(InscritLignePeer::CAT);
    
    $rs = InscritLignePeer::doSelectRS($c);

    $this->inscrit_ligneList = array();
    while ($rs->next())
    {
      $inscrit_ligne = new InscritLigne;
      $colNum = $inscrit_ligne->hydrate($rs);
      $inscrit_ligne->setCatLibelle($rs->getString($colNum));
    
      $this->inscrit_ligneList[] = $inscrit_ligne;
    }

and in your object class :

    public function setCatLibelle($catLibelle='') {
        $this->catLibelle = $catLibelle;
    }
    
    public function getCatLibelle() {
        return $this->catLibelle;
    }