HMVC / MX_Controller / Undefined property

[eluser]Unknown[/eluser]
good eve
I have a similar problem
I get this errors

A PHP Error was encountered

Severity: Notice

Message: Undefined property: CI::$data

Filename: libraries/Controller.php

Line Number: 354


public function __get($var) {
return CI::$APP->$var;

}
}



and

A PHP Error was encountered

Severity: Notice

Message: Indirect modification of overloaded property Bs::$data has no effect

Filename: controllers/bs.php

Line Number: 41

function add(){
$this->load->library('form_validation');
$this->data['custom_error'] = '';


the lines of codes are below. please anyone of help I am using codeigniter 1.7.2 and I got the codes for crud generator which was created with codeigniter 2.0.2