What you found is more or less the best process. The vital step you haven't seemed to mention is the use of a 2nd UV channel. By using a 2nd UV channel, you should not have to change your materials or their application at all. The 2nd UV channel is what will get 'automapped' and Render-to-textured, and it will only hold…
Yeah 2nd UV channel it's common, If that's the best practice then I'm good with that. I set up the materials a certain way though. I used a standard material, and used an rgb multiply in the diffuse slot and plugged in both my texture and a vertex color node. Then I plugged in my lightmap into the self illumination slot…