Weird shading

Hello guys,
I have a Space level and somewhy I get weird shadeings. what I have:

Custom Skybox (Space),
Exp. Height Fog,
Box reflection capture
Post Process,
Crystals (Point Light inside)

For lighting I use the Skylight, Reflection from Skybox, and the crystals.

I worked like 3 hours on it, and after bulding the level I got these weird shaders. (Before building level everything was fine)

What I tried so far:
Increaseing the resolution of the skylight and the static meshes.
Disable reflection capture, crystals, disable lighting from sky, playing with indirect light, smooth, etc…

1 things: With just dynamic directional light there isnt any problem

The only thing I can say: Before building the level/lighting everything was perfect.

OK I made some tests, here are the results (Do not forget, all my lightings are dynamic)

Before build

After build (the color is random…)

I was able to solve it with a little help by 0lento (thank again)
Basically because I just used fully dynamic lighting. Static Lighting had no use, so disabled it in : Editor-Render