How can I force Unity to use my UV2 channel for lightmapping?

Hi All,
Wondering what I'm doing wrong here, I have created 2 uv sets on my geomety in max
Set uv channel 1 for albedo information
Set uv channel 2 for light map - mapping geometry to reduce # of charts and hopefully clean up artifacts and help render times as suggested in the "viking lighting tutorial"
When I import into Unity I make sure "generate Lightmap UV's" is unchecked.
I set everything up, and after scene is baked, I look at the charts in Lighting - Object Maps and the map has been split up to several charts and basically ignoring my UV2 channnel.
In my model I have originally 4 "islands" - unity is giving me roughly 12.

How can I force Unity to use my UV2 channel for lightmapping?
thanks for any help
Jinda

 

I have a similar question.

My 3d scene has meshes that
- have UV2 channel nicely unwrapped
- don´t have UV2 channel at all

Now I want to lightbake the scene in Unity also including the meshes that do not have UV2 channel.
So I tick "Generate lightmap UVs" in Unity to ensure that all meshes have UV2.
But now my custom unwrapped meshes get overwritten by a new UV2 layout by Unity. :-(

I want Unity both to keep my own UV2 layouts and generate UV2 for missing UVs.
Not possible?

At least there should be a toggle "Keep existing UV2", right?