CakeDC Search plugin doesn't work

i'm trying to develop a simple search form using cakedc plugin, i followed step by step the instructions , but i got the next error:

Database Error

Error: SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'validateSearch' at line 1

SQL Query: validateSearch

i don't know what i got wrong, can you help me?, this is what i've got, Thank you. In the Controller:

class ProductosController extends AppController {

public $name = 'Productos';
public $uses = array('Empleado','Cliente', 'Mesa','Producto', 'Productotipo','Productos');  


    public $components = array('Search.Prg');
public $presetVars = true;
public $paginate=array();
public function ventas(){       
    $this->Prg->commonProcess();        
    $this->paginate['conditions'] = $this->Producto->parseCriteria($this->Prg->parsedParams());
    $this->set('productos', $this->paginate());
}

In the Model:

class Producto extends AppModel {
public $name = 'Producto';      
public $displayField = 'productotipos_id';  
    public $belongsTo = array('Productotipo'=>array('className'=>'Productotipo','foreignKey'=>'productotipos_id','conditions'=>'','order'=>''));    
public $actsAs = array('Search.Searchable');    
public $filterArgs = array(
    'nombre' => array('type' => 'like')     
);

In the view

<?php echo $this->Form->create('Producto', array('url' => array_merge(array('action'=>'ventas'), $this->params['pass'])));?>
<fieldset>
    <legend>Pedido</legend>
<?php   

    echo $this->Form->input('Producto.nombre', array('div'=>false,    'empty'=>true));          
    echo $this->Form->submit(__('Search', true), array('div' => false));
    echo $this->Form->end();        
    ?>
</fieldset>

Try to reorder $uses that Controller's model will be the first:

public $uses = array('Producto', 'Empleado', 'Cliente', 'Mesa', 'Productotipo');

Should help. Don't know why, but probably some of methods from CakeDC Search plugin depends on first item in this array.