Hey guys, don’t you know how to use already prerendered lightmaps (in some external program aka Vray) on your objects in Unity?
1 guy told me if I import my FBX file with IDs 1 for diffuse and IDs 2 for lightmap and use legacy lightmap shader it will work, but my lightmap takes ID 1 as well as the diffuse. Where do you set what id what map has? Also the effect of lightmap is visible only in scene window and not in the actual game window 
Could anyone help?
Ty in advance 
Seems like i gotta ask first to figure it out for myself. Going to be quite beginners answer probably, but:
What I did wrong is: I didn’t use “Reset UVWs” option in unwrap modifier in 3ds max after changing IDs on the UNWRAP. What should I do is to use just 1 Unwrap modifier, setup IDs in channel 1, then on the same modifier change IDs to 2, use reset uvws option and remap the object for channel 2 in the unwrap (which is lightmap channel in unity - at least for legacy shaders).
I found this tutorial to be very usefull for this : Creating a 2nd UV channel in 3ds Max - 3dmotive - YouTube
Then everything works fine. Only problems I have now is tuning the lights intensity I use in unity atop to the lightmaps so the lightmaps are not overridden to much etc. But it works fine now 
I was stuck on this for a few days, I hope I’ll at least help somebody else if he has the same problem 