Lightmapping from Maya to Unity3D/3.5, Legacy Shaders?

I may missing some step in the workflow to generate Lightmaps in Maya to use in the Unity. This is what I'm trying to do:

1) I used Maya'11 to created the models and applied the textures and materials using UV Map Channel 1.

2) After that, I created another map in the UV channel 2 to baked the lightmap into (generating TIF images)

This step uses something like this procedure: http://forum.unity3d.com/threads/8998-Making-lightmaps-in-Maya-(tutorial)

3) So I exported the models to Unity3D using FBX.

4) To use the lightmap I use the "Legacy Shader/Lightmapped Diffuse", putting the texture image in the "Base (RGB)" slot and the lightmap TIF image in the "Lightmap (RGB)", and applying the shader to the object.

And this works!

But, I suppose I should not use a Legacy Shader, right?

So how I use the Lightmap without using the Legacy Lightmapped Shader? The others Build-in shadders haven't a "Lightmap (RGB)" slot.

There are another way to use the lightmaps generated in Maya?

Thanks in advance.

Regards