The start points on this map have been displayed with red dots. The position of the bag tag is the bright green splodge on the second floor. Also, this map uses just about all the memory, you won't be able to place more than 10 - 15 guns/armour etc.
And if you are a bit puzzled at the green spray paint on the second floor, it is the walk ways of the type 21 and 22 tile pieces.
Biggs&Wedge recommends using the Industrial tile set for this map.
