Trying to fix $crtDurSettings

[Manaus]

Hello, I'm trying to fix the extension for 2.6.7, but I think it's a bit overhead for me.
The error seems to be at line 92, in_array() expects parameter 2 to be array, null given.
Line 92 is in this block:

foreach ($this->durSettings as $durSetting) {
                $options[] = array(
                    $durSetting,
                    in_array($durSetting, $crtDurSettings),
                    $durSetting
                );
            }

So $crtDurSettings is null. Definition is

$crtDurSettings = $this->get('settings')

Where does it get these settings from? (sorry I'm quite noob, but I'd like to use the extention).
Thanks!