MysticMiner

(for example, suppose that your SP world name is TESTWORLD) i tried this in tekkit [3.1.2] and i just went into the server config, and set world_name=TESTWORLD, then i deleted the old world folders (world_end, world_nether, etc.) and put the single-player map folder in the server folder, and it worked for ME, so if it works for you, AWESOME, if not then try what andrewdonshik^ said if you havent already tried. message me if you have questions, im always happy to help :)