Is there a way to reduce light building time on terrain temporarily?

So here’s my situation: I’m working on a music video, it will be the 3rd one I’ve done so far using Unreal Engine (the 1st was with UE3 and the 2nd was with UDK).

This video will take place on a lake surrounded by some flat-land and then mountains, the stage will be hovering above the lake. I used terrain for the land and mountains, and a plane for the lake water. (Off topic, if anyone has any guides for waves lapping against the shore, hit me up with a link).

I am in the early stages of making the map/scene right now, and I am facing an issue with the lightmass taking forever to build/update the lighting each time due to the size of the map. Attached are pictures of my progress.

My Question:
Is there a way to temporarily disable lighting on the terrain (and painted scenery) so I can focus on the lighting for the instruments that I will add in later? I recall previous iterations of the engine had an option under an actor to “accept lights” that could be unchecked, but I’ve found no such option so far. Anyone have any advice?

PS.
If you need clarification on the purpose of this project, I would defer to my previous two music videos you can find on youtube/rctforme if you need an idea as to what I am trying to create. Note that those two videos do not make use of terrain.

In case anyone was curious, I switched the lights to movable so they’d be treated as dynamic lights, made it so I don’t have to build lighting at all.