You only get an app on notification settings, when you actually get a notification from them. it's the same as Windows Phone, you don't get anything on action center, until you get notifications from it and then you can disable them and change settings.
I wish there was a way to delete them easily, without any hack on registry as it must be (haven't really tried to find a way). because I have 4 autodesk download manager, when I minimized them on each installation I have made, and it told me it was minimized.