CMS Made Simple Forums

I'm using FEU to allow users to log in:
{FrontEndUsers action=login }

After log in they are redirected to a module that I created. How do I get the Loggedid ID?

I've tried this:
$feu = \cms_utils::get_module('FrontEndUsers');
$uid = $feu->LoggedInId();

but I am getting this error message:
Notice: Undefined offset: 1 in C:\wamp64\www\xxxxxx\modules\FrontEndUsers\lib\class.FrontEndUsersManipulator.php on line 66

That is the correct syntax.

But you must be running an old version because line 66 of that file in the latest release is: