PushNotificationDemo for Android fails to build

I have another PushNotification question, sorry to hijack the thread.
In order to display push notification data correctly in my app, I need custom data.
But there are three different ways of receiving notifications:

  1. The app is open.
    The notification contains standard field like title and body. Custom data can be found under properties[“data”][“customKey”].

  2. The app is closed and I click on the Android notification.
    The app will open and a new notification is received. But this time, the data can be found directly under properties[“customKey”].

  3. The app is closed, I receive a notification and open the app directly.
    I get all delivered and unread notifications via PushNotifications::getDeliveredNotifications(). In the async callback I get an array of Notifications. But this time the layout is changed again. It seems these Notifications don’t contain the custom data at all.

My problem is with the last point. Is it not possible to get the custom data at all here?

@lukasz.k any ideas?