Hmm, I guess I need a better way to indicate open doors, eh? For the next version of the map, I'll represent open doors with lighter, dotted lines and closed doors with the double lines.
UPDATE: I've replaced the original map as described. Hopefully this clears things up; Sofia, Karn, and Wyngrad have a line of sight to the first of the two zombies; Layna, Astaban, and Sikhandyn can see both. Methuselah is out in the hallway and thus can't see.