Must be missing something with loading generated maps on a dedicated server. Generated a custom 10k world. Edited relevant section of serverconfig.xml to the following
Copied the generated map to /saves/GeneratedWorlds/Aeths_v19p1_Nitrogen/ and ran the startup script
Nope, server generates it's own map.
Copied the generated map to /Data/Worlds/Aeths_v19p1_Nitrogen/ and ran the startup script.
Nope, server generates it's own map.
Since the server insists on making the map "Seciha County" in generated worlds, I deleted the generated stuff and copied my custom map over. Now it seems to be working.