Does Unity generate correct AndroidManifest.xml?

This should help, im still in the process of solving the 'Certificate is a debug cert' issue

Android Application Signing and Unity

Unity automatically signs Android applications with a temporary debug certificate by default. Before building your final release build, create a new Android keystore and assign it with the Use Existing Keystore option, found in Edit > Project Settings > Player > Publishing Options. For more information, see the “Android” section of Unity's documentation here:http://docs.unity3d.com/Manual/class-PlayerSettings.html.