I realized I should probably specify a bit more about the layout of the Hall of Justice since we'll soon be having a giant battle there that might spill out into other parts of the building. So, I drew up a quick reference in Paint. This is not at all to scale, it just adds a little bit of a visual reference to the description of the layout I had given in the intro post. I'll quote that part here along with the image. The small blocks along the top of the image, just north of the Utility Hallway, represent various offices and storage spaces. The one marked [i][b]"SO"[/b][/i] is the Security Office Batman takes them to. 

[quote=@CaptainManbeard]
The Justice League’s Tenth Anniversary Celebration was expected to be one of the biggest social gatherings of the Summer, attracting celebrities, media personalities, and even politicians. It was also coinciding with the grand re-opening of the Hall of Justice, which had been remodeled and converted into a museum and event space since the League now used the Watchtower satellite as their new headquarters. 

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Both costumed heroes and uniformed security personnel were managing the flow of people into the building, which opened into a spacious lobby with polished marble floors and support pillars of white stone and gold trim. Long halls extended to the left and right, with map displays showing how to get to the various museum exhibits, gift shops, restrooms, conference rooms, kitchens, food court, etc. 

Giant stone statues of the founding League members lined the far wall, and between each one was a set of double doors which all opened into the enormous Grand Ballroom. A sea of round tables sat facing a stage, not unlike what one might see at the Golden Globes. Hundreds of people were coming back and forth, finding their chairs or heading out to see other parts of the Hall before the main event started. 
[/quote]

[center][img]https://i.imgur.com/XR4st8M.png[/img][/center]