Trying to setup moving NPC's on my aim train server but i can't figure out how to get them to start moving i understand how to setup waypoints to create the npcs a path to walk but when i test there walking path just gives me a error in console?

Failed to call hook 'cmdChatNPCPathTest' on plugin 'HumanNPC v0.6.5' (NullReferenceException: )
  at (wrapper managed-to-native) UnityEngine.Component.get_transform(UnityEngine.Component)
  at Oxide.Plugins.HumanNPC.cmdChatNPCPathTest (BasePlayer player, System.String command, System.String[] args) [0x00056] in <67ee59df6b574c62a8e8f09b91ed8a21>:0

  at Oxide.Plugins.HumanNPC.DirectCallHook (System.String name, System.Object& ret, System.Object[] args) [0x01279] in <67ee59df6b574c62a8e8f09b91ed8a21>:0

  at Oxide.Plugins.CSharpPlugin.InvokeMethod (Oxide.Core.Plugins.HookMethod method, System.Object[] args) [0x00079] in <42f9bedc659b4f4786eb778d3cd58968>:0

  at Oxide.Core.Plugins.CSPlugin.OnCallHook (System.String name, System.Object[] args) [0x000de] in <112d89ea5d3348c8b949af0ab1a866d2>:0

  at Oxide.Core.Plugins.Plugin.CallHook (System.String hook, System.Object[] args) [0x00060] in <112d89ea5d3348c8b949af0ab1a866d2>:0

Really need help figuring this out! I don't understand how to create proper navmesh that NPC's can walk on as that can't be done on RustEdit to my knowledge, en less im mistaken.