getting things working after taking develop merge. The MLAPI dependency was unhappy. I've changed the path to something that doesn't 404 for me, and updated the commit hash to the current head of the develop branch (in the mlapi repo)

Packages/packages-lock.json

 {
   "dependencies": {
+    "com.unity.burst": {
+      "version": "1.3.7",
+      "depth": 2,
+      "source": "registry",
+      "dependencies": {
+        "com.unity.mathematics": "1.2.1"
+      },
+      "url": "https://packages.unity.com"
+    },
     "com.unity.collab-proxy": {
       "version": "1.3.9",
       "depth": 0,
     },
+    "com.unity.collections": {
+      "version": "0.14.0-preview.16",
+      "depth": 1,
+      "source": "registry",
+      "dependencies": {
+        "com.unity.test-framework.performance": "2.3.1-preview",
+        "com.unity.burst": "1.3.7"
+      },
+      "url": "https://packages.unity.com"
+    },
     "com.unity.ext.nunit": {
       "version": "1.0.0",
       "depth": 1,
       "dependencies": {},
       "url": "https://packages.unity.com"
     },
+    "com.unity.mathematics": {
+      "version": "1.2.1",
+      "depth": 3,
+      "source": "registry",
+      "dependencies": {},
+      "url": "https://packages.unity.com"
+    },
-      "dependencies": {},
-      "hash": "8e7e3ca556843794618ab91c6b8334b291ff4e3d"
-    },
-    "com.unity.multiplayer.transport.litenet": {
-      "version": "file:com.unity.multiplayer.transport.litenet",
-      "depth": 0,
-      "source": "embedded",
-        "com.unity.multiplayer.mlapi": "0.0.1-preview.1"
-      }
+        "com.unity.collections": "0.14.0-preview.16"
+      },
+      "hash": "726b77f90f2bb2879303cf72a22048ac0abf4084"
     },
     "com.unity.multiplayer.transport.litenet": {
       "version": "file:com.unity.multiplayer.transport.litenet",
         "com.unity.multiplayer.mlapi": "0.0.1-preview.1"
       }
     },
+    "com.unity.nuget.newtonsoft-json": {
+      "version": "2.0.0-preview",
+      "depth": 3,
+      "source": "registry",
+      "dependencies": {},
+      "url": "https://packages.unity.com"
+    },
     "com.unity.test-framework": {
       "version": "1.1.16",
       "depth": 0,
         "com.unity.modules.imgui": "1.0.0",
         "com.unity.modules.jsonserialize": "1.0.0"
+      },
+      "url": "https://packages.unity.com"
+    },
+    "com.unity.test-framework.performance": {
+      "version": "2.3.1-preview",
+      "depth": 2,
+      "source": "registry",
+      "dependencies": {
+        "com.unity.test-framework": "1.1.0",
+        "com.unity.nuget.newtonsoft-json": "2.0.0-preview"
       },
       "url": "https://packages.unity.com"
     },

Assets/Scripts/NetworkingManagerHUD.cs

-using UnityEngine;
-using MLAPI;
-
-[RequireComponent(typeof(NetworkingManager))]
-public class NetworkingManagerHUD : MonoBehaviour
-{
-    void OnGUI()
-    {
-
-        GUILayout.BeginArea(new Rect(10, 10, 300, 300));
-        if (!NetworkingManager.Singleton.IsClient && !NetworkingManager.Singleton.IsServer)
-        {
-            StartButtons();
-        }
-        else
-        {
-            StatusLabels();
-        }
-
-        GUILayout.EndArea();
-    }
-
-    void StartButtons()
-    {
-        if (GUILayout.Button("Host")) NetworkingManager.Singleton.StartHost();
-        if (GUILayout.Button("Client")) NetworkingManager.Singleton.StartClient();
-        if (GUILayout.Button("Server")) NetworkingManager.Singleton.StartServer();
-    }
-
-    void StatusLabels()
-    {
-        string mode = NetworkingManager.Singleton.IsHost ? "Host" : NetworkingManager.Singleton.IsServer ? "Server" : "Client";
-
-        GUILayout.Label("Transport: " + NetworkingManager.Singleton.NetworkConfig.NetworkTransport.GetType().Name);
-        GUILayout.Label("Mode: " + mode);
-    }
-}
-

Assets/Scripts/NetworkingManagerHUD.cs.meta

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Packages/com.unity.multiplayer.transport.litenet/Runtime/LiteNetLib/LiteNetLib.csproj.meta

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