Unity Ad Documentation.... am I in the wrong place or is this it?

Every page tells you to use the asset store package an points here for doccumentation: http://unityads.unity3d.com/help/Do...shers/Integration-Guide-for-Unity-Asset-Store

I tried to learn using this and couldn't get it going so I used the example script and even that gave me errors when the advertisement attempts to show. Yes, I have placed my game ID, but I'm unsure how to 'test' ads without the app being in the play store.

I get the following error in one of the scripts that came with it:

NullReferenceException: Object reference not set to an instance of an object
UnityEngine.Advertisements.Engine.Show (System.String zoneId, UnityEngine.Advertisements.ShowOptions options) (at Assets/Advertisements/Mediation/Engine.cs:67)
UnityEngine.Advertisements.Advertisement.Show (System.String zoneId, UnityEngine.Advertisements.ShowOptions options) (at Assets/Advertisements/Advertisement.cs:27)