a bare bones data loading / saving (for game levels, savegames, etc.) example using the built-in binary serialization in Unity... I'd suggest hooking it up to the file browser OnGUI thing here: http://forum.unity3d.com/attachment.php?attachmentid=87628&d=1392756207 (from http://forum.unity3d.com/threads/84601-File-Browser/page2)

FileManager.cs

using System;
using System.Runtime.Serialization;
using System.Runtime.Serialization.Formatters.Binary;
using System.Reflection;
using System.Text;
using System.IO;

using UnityEngine;
using System.Collections;
using System.Collections.Generic;

public class FileManager : MonoBehaviour {

	SceneData SceneSave() {
	    // insert whatever data you want to save in a class of type SceneData
	}
	  
	void SceneLoad (SceneData data) {
	    // take whatever data is in SceneData and Instantiate objects, etc. based on it
	}
  
	void FileSave (string fileName) {
		SceneData data = SceneSave();
		Stream stream = File.Open(fileName, FileMode.Create);
		BinaryFormatter bformatter = new BinaryFormatter();
		AddSurrogates (bformatter);
		bformatter.Binder = new VersionDeserializationBinder(); 
		Debug.Log ("SAVING: " + fileName);
		bformatter.Serialize(stream, data);
		stream.Close();
	}
	
	void FileLoad (string fileName) {
		SceneData data = new SceneData();
		Stream stream = File.Open(fileName, FileMode.Open);
		BinaryFormatter bformatter = new BinaryFormatter();
		AddSurrogates (bformatter);
		bformatter.Binder = new VersionDeserializationBinder(); 
		Debug.Log ("LOADING: " + fileName);
		data = (SceneData)bformatter.Deserialize(stream);
		stream.Close();

		SceneLoad (data);
	}
	
	// from http://msdn.microsoft.com/en-us/magazine/cc188950.aspx
	void AddSurrogates ( IFormatter formatter) {
		SurrogateSelector ss = new SurrogateSelector();
		
		ss.AddSurrogate(typeof(Vector3), new StreamingContext(StreamingContextStates.All), new Vector3Surrogate());
		// NOTE: AddSurrogate can be called multiple times to register
		// more types with their associated surrogate types, for when
		// you make more ISerializationSurrogates to implement for your
		// UnityEngine types...
		
		formatter.SurrogateSelector = ss;
	}
}


[System.Serializable]
public class SceneData : ISerializable {
	// put your data here
	public string name = "New Scene";
	
	// serialization methods implemented by ISerializable
	public SceneData (SerializationInfo info, StreamingContext ctxt) {
		//Get the values from info and assign them to the appropriate properties
		name = (string)info.GetValue ("name", typeof(string) );
	}
	
	public void GetObjectData (SerializationInfo info, StreamingContext ctxt) {
		info.AddValue ("name", name);
	}
}


// example of a serialization surrogate you would need to implement for any custom classes or UnityEngine types
public class Vector3Surrogate : ISerializationSurrogate {
	public void GetObjectData(object obj, SerializationInfo info, StreamingContext context) {
		Vector3 vec = (Vector3)obj;
		info.AddValue("x", vec.x);
		info.AddValue("y", vec.y);
		info.AddValue("z", vec.z);
	}
	
	/// This method is part of the interface ISerializationSurrogate
	public object SetObjectData(object obj, SerializationInfo info, StreamingContext context, ISurrogateSelector selector) {
		Vector3 vec;
		vec.x = (float)info.GetValue("x", typeof(float));
		vec.y = (float)info.GetValue("y", typeof(float));
		vec.z = (float)info.GetValue("z", typeof(float));
		obj = vec;
		return obj;
	}
}


public sealed class VersionDeserializationBinder : SerializationBinder 
{ 
	public override Type BindToType( string assemblyName, string typeName )
	{ 
		if ( !string.IsNullOrEmpty( assemblyName ) && !string.IsNullOrEmpty( typeName ) ) 
		{ 
			Type typeToDeserialize = null; 
			
			assemblyName = Assembly.GetExecutingAssembly().FullName; 
			
			typeToDeserialize = Type.GetType( String.Format( "{0}, {1}", typeName, assemblyName ) ); 
			
			return typeToDeserialize; 
		} 
		
		return null; 
	} 
}