you probably have not much experience with detailed indoor scenery and scene-management. If you make it with A7 and ABT scene manager then all the rooms in camera view will be rendered even if they are behind a wall. The amount of models and polygons is huge then.

ABT is good for outdoor but useless for indoor. The A7 pro BSP does not run smooth with shaders.

In C4 the system renders only the zone you are visiting. Many engines use such zone / portal system like Lawmaker, Torque, Unreal. Sometimes it is combined with a BSP (but still with user defined portals).

But if you really can do that then dont talk, just do it and make a contribution of that level. We all would be happy to see it with shaders applied.