There's a lot of light bleeding through walls under ledges.
Yes, but the lighting in that scene is probably rendered with the standard global illumination settings, which are there to provide speed, and not precise renders. By tweaking the parameters, it should be possible to remove such artefacts. And if not, you can always touch them up by painting over the errors :) ...concave edges in the parking garage screenshot. It's hard to see though cause you used high res light maps...
If it's the top screenshot you're talking about, then the lightmap for all the geometry together is 256x256, hardly hires...But I do have a few tricks up my sleeve, so I may be able to remove it completely :)