Lighting Issues

[Eiii]

So I was making this map, and compiling it. And it compiled, and was beautiful.

THEN ALL OF A SUDDEN, I compiled it again, and none of the light bounces. How do I know? The ceiling is black.

I didn't touch the BATs or anything, and now there's no more pretty.

Halp?

EDIT: Oh, there was a leak. Which is odd, because it's a box at the moment. And I didn't know maps would light with leaks.
EDIT2: Aaand I managed to move a wall over 4 units. Odd.

[sk89q]

Lighting is really odd with a leak. There are more dark places.

[Eiii]

That's because there's no bounced light.