Facepalm

Aye, I saw it. If you assume that building 1 was the first built, then 2 and 3 were added afterwards so they were numbered from left to right, and finally building 4 was built last behind everything else the building numbers are fine.

If you assume the legend was for the order to visit the buildings in, starting at number four (the newest, perhaps with a meeting space in it), then move clockwise until all the buildings have been visited you would walk in 4, 3, 1 2 order.

Without that context of visiting the buildings clockwise, the legend seems insane and disjointed. With it, well it's not much better but at least I can see why it happened.