Lighting is not blending between ceiling tiles

I’m using the assets from the Reflections project to learn how to better use the program and I’ve come into a problem I can’t solve. The ceiling tiles are not blending their light together. Here as an image of the situation:

Any idea what I should do? Thanks!
EDIT: I have lightmass importance volume surrounding the room, I have ceiling override the light map res at 128, casting shadows is disabled, and the tiles for the ceiling are the ones used for the ground, I just flipped them.

Hi Tyjaco,

Take a look at this thread on the forums. Just about everything is laid out here to explain reasons for this: Modular Asset Lighting Problem - Rendering - Epic Developer Community Forums