Update some comments

src/MonoTorrent/MonoTorrent.Client/Settings/EngineSettingsBuilder.cs

@@ -157,15 +157,16 @@ public int DiskCacheBytes {
 
         /// <summary>
         /// The UDP port used for DHT communications. Use 0 to choose a random available port.
-        /// Choose -1 to disable DHT. Defaults to 52139.
+        /// Choose -1 to disable DHT. Defaults to 0.
         /// </summary>
         public int DhtPort {
             get => dhtPort;
             set => dhtPort = CheckPort (value);
         }
 
         /// <summary>
-        /// The TCP port the engine should listen on for incoming connections. Defaults to 52138.
+        /// The TCP port the engine should listen on for incoming connections. Use 0 to choose a random
+        /// available port. Choose -1 to disable listening for incoming connections. Defaults to 0.
         /// </summary>
         public int ListenPort {
             get => listenPort;

src/SampleClient/main.cs

@@ -28,16 +28,43 @@ static void Main (string[] args)
 
         static async Task MainAsync (string[] args, CancellationToken token)
         {
-            Task task;
+            // Give an example of how settings can be modified for the engine.
+            var settingBuilder = new EngineSettingsBuilder {
+                // Allow the engine to automatically forward ports using upnp/nat-pmp (if a compatible router is available)
+                AllowPortForwarding = true,
+
+                // Automatically save a cache of the DHT table when all torrents are stopped.
+                AutoSaveLoadDhtCache = true,
+
+                // Automatically save 'FastResume' data when TorrentManager.StopAsync is invoked, automatically load it
+                // before hash checking the torrent. Fast Resume data will be loaded as part of 'engine.AddAsync' if
+                // torrent metadata is available. Otherwise, if a magnetlink is used to download a torrent, fast resume
+                // data will be loaded after the metadata has been downloaded. 
+                AutoSaveLoadFastResume = true,
+
+                // If a MagnetLink is used to download a torrent, the engine will try to load a copy of the metadata
+                // it's cache directory. Otherwise the metadata will be downloaded and stored in the cache directory
+                // so it can be reloaded later.
+                AutoSaveLoadMagnetLinkMetadata = true,
 
-            using var engine = new ClientEngine ();
+                // Use a random port to accept incoming connections from other peers.
+                ListenPort = 0,
 
+                // Use a random port for DHT communications.
+                DhtPort = 0,
+            };
+            using var engine = new ClientEngine (settingBuilder.ToSettings ());
+
+            Task task;
             if (args.Length == 1 && MagnetLink.TryParse (args[0], out MagnetLink link)) {
                 task = new MagnetLinkStreaming (engine).DownloadAsync (link, token);
             } else {
                 task = new StandardDownloader (engine).DownloadAsync (token);
             }
 
+            if (engine.Settings.AllowPortForwarding)
+                Console.WriteLine ("uPnP or NAT-PMP port mappings will be created for any ports needed by MonoTorrent");
+
             try {
                 await task;
             } catch (OperationCanceledException) {
@@ -57,6 +84,9 @@ static async Task MainAsync (string[] args, CancellationToken token)
 
             if (engine.Settings.AutoSaveLoadDhtCache)
                 Console.WriteLine ($"DHT cache has been written to disk.");
+
+            if (engine.Settings.AllowPortForwarding)
+                Console.WriteLine ("uPnP and NAT-PMP port mappings have been removed");
         }
     }
 }