I changed the lights and removed the blockings from the windows (now you can jump through of them.)
I'm currently waiting for the download links to be updated.
Edited 2.73 hours after the original posting.
Maybe some -gamma and -compensate compiling cuold help clamp the overbrights while bringing a fuller lighting balance. Doom didn't have overbrights, but it didn't have a real lighting system either. Might help to get lighting inspiration from running Doom in an older version of Vavoom since that builds lightmaps for its quake-derived renderer.
Edited 3.03 minutes after the original posting.