If you get stuck on Room Lighting post a screenshot of what you setup and I can give some tips. You should be able to do what you want for the on/off as well.
Another option, which may actually be the absolute easiest is the custom switch bindings app. It basically is designed to create virtual 3/4 way setups with multiple smart switches. It can do multi-switch bi-directional state mirroring. Disadvantage over room lighting is you cant do much else with it, it just mirrors the states. But if that's all you want to do it will work good.
