iSTD.cs

// An example snippet for: https://www.quizcanners.com/single-post/2018/04/20/Story-Trigger-Data-Interface-iSTD

public stdEncoder Encode() => new stdEncoder()
  .Add("mrkP", mapMarkerPosition);
  .Add("mrkC", mapMarkerColor);

public bool Decode (string tag, string data){
  switch (tag){
    case "mrkP": mapMarkerPosition = data.ToVactor2(); break;
    case "mrkC": mapMarkerColor = data.ToColor(); break;
    default: return false;
  }
  return true;
}

// In case class structure changed, but you want to preserve backwards compatibility:

// In Encode() fucntion:
if (mapMarker.enabled){
  cody.Add("mrkP", mapMarker.position);  
  cody.Add("mrkC", mapMarker.color);  
}

// In Decode Function
case "mrkP":  
  mapMarker.enabled = true;
  mapMarker.position = data.ToVector2();  
case "mrkC":
  mapMarker.color = data.ToColor();
  UpdateMarkers();
  break; 

// But if BackwardsCompatibility is not needed you should add Encode()/Decode() functions and iSTD interface to MapMarker class
// and replace the functions above with something like:

public stdEncoder Encode() => new stdEncoder()
  .Add("mrk", mapMarker); // This will call Encode() in the mapMarker, and will get position and color;


public bool Decode (string tag, string data){
  switch (tag){
    case "mrk": mapMarker.Decode(data); break;
    default: return false;
  }
  return true;
}

// This way you can manually save any data for any class, without creating any additional Serializable classes.