What needs to be done after In Stock Reminder app installation?

What does such statuses as and mean in Notifications section?

Is it possible to customize emails?

Why my clients get notifications from no-reply@spuritmail.com, and not from the e-mail indicated in Email Templates section?

How to verify my email address?

Is it possible to use In Stock Reminder app together with your other apps (e.g. Unlimited Upsell)?

What needs to be done to remove In Stock Reminder app completely?