Your map has
MANY leaks!! It's a record!
You need to know that Doors and Buttons don't block areas from the void, resulting in leaks. The same for Patches.
Pics:There is a door where my camera is here:

Reduce those patches so they don't surpass the ceiling and the floor:

Stupid:

Doors/Buttons don't block from the void:

There are many more leaks I don't had patience to make pics.
Observing your map, I can say you were some lazy when making your brushes: many are bad aligned, overlapping, redundant (can merge some) etc. etc. etc.
You don't use any Caulk shader but many NULL textures...
Make sure you use some Detail brushes too.
Don't be lazy! Keep working! That map can be turned into a good one. Big map, big challenge.