Infection Free Zone - Finding Area 51

I have found the location for "Area 51" in game. Unfortunately, the area is too resource poor for the game to acknowledge it as a suitable area to play in.
If you do select this area, it will recommend that you install and use the map editor. The game will point you to the proper Steam file, you just have to install it. Then, if you click the location again, you can click "Open With Map Editor".
Unfortunately, I just don't have the time right now to sift through map assets or to figure at how to add buildings and features, at this time. Plus it sort of ruins the point of trying to build in real locations if you have to modify it.
With that being said, I am sure people could find it fun to try and create underground facilities, using little buildings on the surface, like how the Haunted Mansion in my Disneyland play through seems to have a larger underground facility under it...