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…
Does the indirect diffuse reflection happen automatically or does it need to be setup? Here's a really bad example of a lightmap generated using Flatiron, The lights are primarily whitish blue.
Lightmaps will contain colour from your lights and from indirect diffuse reflections. (Bounced light) if you have coloured objects in your scene they will have an affect on the lights colour. even if your using pure white lights (which your shouldnt)
It depends what your rendering with. It looks like your using light tracer. Which supports light bounces but does it very slowly. you need to turn up the bounce number in the light tracer options.(or is it bleed.. its one of the two) Personally I'd use mental ray for it. Set your FG to low/Medium, turn off noise reduction…
Where on earth did you hear that? Lightmaps should allways contain colour information. A nice way to do it in max is to put your map in the self illumation slot, turn on 'Color' under the 'self illumation group' in 'basic blinn parameters' to setup the map create RGB multiply node and multiply the lightmap by the diffuse…