Well, a couple of things could cause this problem.
The map is too large for your computer to handle.
The map has too much lag.
You didn't read the ReadMe and misplaced a file or two.
I would recommend just erasing everything from your exports folder and just try to download the working map. And if the map doesn't work, wait a couple days or hours and try again. If it still doesn't work then you either mixed up the files of the map, it is too large, or there is too much lag.
Good luck.