I downloaded/installed the old factions world into singleplayer. It worked- it appeared in the world list. I don't know if it spawned me in an unused area, but there where no signs of what the world was on the server ANYWHERE. Was it a download of the seed, did I spawn in a random area, or did something go wrong? Note: I did both downloads and it worked, except no buildings/signs of players' usage anywhere.
Thank you! I was excited to have this map, but I didn't know what was going on because I was in a patch of wilderness. I did a calculation from the stats Jerry gave, and the map is 900,000,000 square blocks. Apparently I have some traveling to do. I might make a series out of it...