Meaning of NetworkManager Warnings

Can anybody tell me what the warnings are all about?
I get them from the NetworkManager with LogLevel = Debug when I create a LAN host:

Ready with no player object
UnityEngine.Networking.NetworkIdentity:UNetStaticUpdate()

ClientScene::InternalAddPlayer: playerControllerId : 0
UnityEngine.Networking.NetworkIdentity:UNetStaticUpdate()

The strange thing is that the game runs fine on editor but it crashes on a build.