thanks for taking time to write this perfect answer
yes this is 3ds max 2016 and vray 3.2
i guess i can use ( VRayMtl Converter ) Script to covert the materials back into standard ( will that speed up the process ?)
i start to arrange the layer in 3d max and naming the objects , it took all day and i didn’t finish yet , so it is going to be brutal indeed
thanks for the last notice , most my floor and wall is one plane so i can add shell modifier ( will that be enough ? )