The only thing you can do is test the map and see where stuff actually spawns. Some maps are just bugged, and the only way to know if the map is messed up, and exactly how, is to place objects and bosses in each section, then go in and see where they actually show up.
Best way to do this is to create 3 objects, name them Front, Middle, and Back, then place them in those locations, then do the same with 3 boss objectives. Note that the boss and objective spawns are separate, and one can be messed up or work without affecting the other. Once you have which location each thing spawns, it will be consistent for that map. (Until they get around to fixing the spawn points and screwing up thousands of arcs of course. 
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This is the major reason to not use random maps for your arcs, if it is important where and in what order players interact with your objectives. And remember that despite what it shows on the map, there is no Front/Middle/Back on outside maps. All spawn points there are completely random.
Justice Blues, Tech/Tank, Inv/SS
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Fighting The Future Trilogy
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Hey everyone, I'm new to MA and I have a small problem.
My first mission "Condemned", requires players to find two objects. I selected putting one in the middle and one at the end, intending players to hit the last room
I'm sure everyone know the system of Green = Front, White = Middle, Red = End.
Well, while the first object shows up near the start of the second of three floors, right in the middle, the object I selected to place at the end shows up on the second floor, in a white area as well instead of the final, red room.
How can I fix this?