Trouble running PHP in general

Hello, I am running into some serious trouble running PHP on my server. Ultimately I have, for example, this array:

$app_vars

which has these values (which i tested)

Array
(
    [controller] => index
    [action] => patients
)

the "index" file then has this:

switch ($app_vars["action"]) {      
      case "admin":
            $msg = 'MedLab Results Administration Login';
            $Presenter->assign('page_title', 'MedLab Results Administration Login');
            $Presenter->assign('alert', $alert);
            $Presenter->assign('msg', $msg);
            $Presenter->display('admin.tpl');
            Session::cleanMessage();
            break;
      case "patients":
            $msg = 'The Benefits of MedLab Results For Patients.';
            $Presenter->assign('page_title', 'MedLab Results: Benefits For Patients');
            $Presenter->assign('alert', $alert);
            $Presenter->assign('msg', $msg);
            $Presenter->display('patients.tpl');
            echo 'test';
            Session::cleanMessage();
            break;
      case "doctors":
            $msg = 'The Benefits of MedLab Results For Doctors.';
            $Presenter->assign('page_title', 'MedLab Results: Benefits For Doctors');
            $Presenter->assign('alert', $alert);
            $Presenter->assign('msg', $msg);
            $Presenter->display('doctors.tpl');
            Session::cleanMessage();
            break;
      default:
            $msg = 'Welcome to MedLab Results!';
            $Presenter->assign('page_title', 'MedLab Results: Web Solutions for ' .
                                                            'Doctors and Patients Powered by Akuesoft');
            $Presenter->assign('alert', $alert);
            $Presenter->assign('msg', $msg);
            $Presenter->display('index.tpl');
            
            Session::cleanMessage();
            break;
}

and whats odd is that the entire switch statement is ignored, anything I put after the switch statement doesnt work, and the Presenter object doesnt work, which extends Smarty. I checked my error logs, and nothing. I AM COMPLETELY PUZZLED.Start Free Trial