except the ceiling, I lined up everything perfectly so no object is moving pass others. So all the walls in the scene are touching the floor and nothing is scaled in unreal. Regarding the shadow bleeds I saw that happening so I broke down the ground to smaller segments and that helped with the bleeds.
I initially created single piece walls for each segment and I had to do light-map and texture UV layouts for each wall. In the end when I wanted to modify something small I had to create new walls. So after that I tried using small piece walls which as far as work flow it’s much faster for me BUT I guess it comes down to preference.
so you are saying there is no way to get rid of the artifacts using small segments ?