Some basic questions on UE4

Hello guys!
Can someone experineced, help me with a few things please?

-Is it possible to have dynamic shadow for the character, from “static” lights somehow? Or the only way - is to have “stationary” lights?
-We’ve got a “movable door” blueprint. The door - is a skeletal object, with bone-driven animation. The problem is - the lighting for that door is looks completely different, compared to a regular geometry objects. Why?
-Even when having all lights “dynamic”, the “light building” for the semi-open world map is taking a lot of time\resources. Why?
-Is there any way to optimize “dynamic/stationary” lights, rather than use “max draw distance”? Like decrease the shadow resolution, or use only selected objects to recieve shadows?
-When using “stationary” sun\skylight - is it baking lightmaps for the “static” geometry objects?

-We are using 1 huge “foliage instance” actor, where all the trees\grass are located. After the light build - i’m getting errors on that (the actor is too huge). In any dark areas - the foliage is always bright, like it’s not reacting to the level lighting properly.
Questions: how to “split” this foliage instance to a smaller pieces? Is it going to help with the shadows?

-No, the only way to get dynamic shadows on something is from stationary or movable lights.
-The static geometry is getting indirect lighting, which is something that’s not being calculated in real-time for the dynamic objects, instead there’s a system where it will render a simple light probe and use that to add ambient lighting to the mesh. In a more recent version of UE4 they added Volumetric Lightmaps, where it renders a grid of probes and then can blend between them across a mesh:
-You can disable the baked lighting entirely by going to World Properties and in the Lightmass section check Force No Precomputed Lighting
-You can do some changes to the cascaded shadow maps here: Dynamic Scene Shadows | Unreal Engine Documentation
-When using stationary lights the indirect lighting is baked into lightmaps and renders direct lighting into distance field shadowmaps
-Not sure, you may need to split things up a bit

But how can i “split” the Foliage Instance actor? To a few different actors?