(1) is where the Minotaur and five Duergar Rogues ran past. (2) is the spot where Lester created the stone portcullis, and later where the Blade Barriers appeared. (3) is where the battle took place. (4) is the staircase where Captain Ironhaul and his rescue team ascended from the 4th Underground level.
(1) is the site of the Khör Dwarf and Umber Hulk fight. (2) is the fight in the Common Room. (3) is where the Heroes met the “Dwarf Scout” who gave them intel about the Duergar Commander group in the Tavern.