Two lightmaps in the same scene - Unity 5

I have only a scene for my game - it's easier to edit the whole game, and the transitions between screens are instantaneous. But now after I've switched to Unity 5, I can't make 2 lightmaps for different levels in the same scene.
Did anyone find a simple workaround for this problem?
No matter how many lightmaps I bake, the same LightmapSnapshot keeps overriding all the light settings from the scene.

 

It should work with Baked GI only. If the scene contains Realtime GI also, it will not work.

 

I only want Baked GI. The problem is that Baked Selected button is gone in Unity 5. So I enable and disable different maps and only bake them. After I bake a map, I move the texture and the LightmapSnapshot in a different folder, and rebake a different map.
On each map I have a script that changes the current lightmap:

Code (CSharp):

1. using UnityEngine;
2.  
3. [ExecuteInEditMode]
4. public class LightmapEnable : MonoBehaviour
5. {
6.     public Texture2D lightmapFar;
7.     public Texture2D lightmapNear;
8.     private LightmapData[] _lightmapDatas;
9.     public LightmapData[] lightmapDatas
10.     {
11.         get
12.         {
13.             if ((lightmapFar != null || lightmapNear != null) && _lightmapDatas == null)
14.             {
15.                 _lightmapDatas = new[] { new LightmapData { lightmapFar = lightmapFar, lightmapNear = lightmapNear } };
16.             }
17.             return _lightmapDatas;
18.         }
19.     }
20.     void OnEnable()
21.     {
22.         LightmapSettings.lightmapsMode = LightmapsMode.NonDirectional;
23.         if (lightmapDatas != null)
24.             LightmapSettings.lightmaps = lightmapDatas;
25.     }
26.     void OnDisable()
27.     {
28.         if (LightmapSettings.lightmaps.Length > 0 && lightmapDatas != null && LightmapSettings.lightmaps[0].lightmapFar == lightmapDatas[0].lightmapFar)
29.             LightmapSettings.lightmaps = null;
30.     }
31. }
32.  

This worked in Unity 4.x but it does not work anymore in Unity 5.
I guess the UV info is lost once a new bake is done in the scene.
If you find a simple solution, let me know.