Most other windows start centered in the main builder window. With multiple displays, windows would start in odd locatins and would often be lost.

EduNetworkBuilder/FirewallEditor.cs

@@ -168,5 +168,15 @@ namespace EduNetworkBuilder
                 lbRules.ContextMenuStrip.Show(Cursor.Position);
             }
         }
+
+        private void FirewallEditor_Shown(object sender, EventArgs e)
+        {
+            BuilderWindow BW = NB.GetBuilderWin();
+            if (BW != null)
+            {
+                Point tLocation = new Point(BW.Location.X + ((BW.Width - Width) / 2), BW.Location.Y + ((BW.Height - Height) / 2));
+                Location = tLocation;
+            }
+        }
     }
 }