Hi,
First, I don’t know if the term “multi-layered” is convenient, as I don’t know if the solution to my problem will come from Layers in Unity. I also must confess I’m quite new with U3D, but I have good programming skills (C++, Flex, js). Well, to the point now! 
We (I and a designer) wish to set a game environment that could have different aspects, though the global design would remain the same. Say, for example, that the primary look’n’feel of the universe would be a futuristic one set in 2077, but the protagonist would have the power to turn parts of that universe back in a 1980 look’n’feel. I am wondering as how to achieve that. My first idea was to use layers, but I am not sure that it would be the best way to do it, performance regarding. So, well, any advice is welcome. Is my first intuition right? Or is there a better way to do it?
TIA,
Cyrill
This may be relevant to you: http://www.youtube.com/watch?v=lHmzDV1rxII
Personally I havent thought much about it, but I think you’re on the right direction, Layers could be one way to do it.
thanx a lot for your answer. I feel relieved to be on the - seemingly - right way! As I don’t know yet how to work with layers at such a level, would it mean to have gameObjects in double (one copy of each per layer)? or could it be just the applied skinning that would be doubled?
I would probably go for the first option, but I am not sure it is the most optmized option.
Thanks a lot for the taking the time to answer!