XML doens't load in Unity Standalone

I'm developing a Turn Based System RPG with Tiled Map loaded from a map.xml file.

I save and load the xml with this code:

 public static void Save(MapXMLContainer mapContainer, string fileName){
         var serializer = new XmlSerializer(typeof(MapXMLContainer));
         using(var stream = new FileStream(fileName, FileMode.Create)){
             serializer.Serialize(stream, mapContainer);
         }
     }
 
     public static MapXMLContainer Load(string fileName){
         var serializer = new XmlSerializer(typeof(MapXMLContainer));
         using(var stream = new FileStream(fileName, FileMode.Open)){
             return serializer.Deserialize(stream) as MapXMLContainer;
         }
     }

 <code>

The path I'm setting is (Application.dataPath + "/map.file"), and if the file is inside the Assets folder, in Editor it's working well. But if I build, the xml file doens't load, even if I put the map.file inside the GameApplication_Data. I've tryed to use the StreamingAssets folder, and it doens't work as well.

I know if I Load from Resources, I could load it without many problems but I cannot get the return value of Resources.Load() as XML and get the proprietes from my xml file that I define here:

 <pre>
 
 [XmlRoot("MapCollection")]
 public class MapXMLContainer{
     [XmlAttribute("size")]
     public int size;
     [XmlArray("Tiles")]
     [XmlArrayItem("Tile")]
     public List<TileXML> tiles = new List<TileXML>();
 }
 
 <code>

How can I load the xml file in my builded project? Thank you for the help.