java.lang.NullPointerException: Exception in server tick loop
	at net.minecraft.world.WorldServerMulti.<init>(WorldServerMulti.java:18)
	at org.spongepowered.common.world.WorldManager.createWorldFromProperties(WorldManager.java:793)
	at org.spongepowered.common.world.WorldManager.loadAllWorlds(WorldManager.java:759)
	at net.minecraft.server.MinecraftServer.func_71247_a(MinecraftServer.java:330)
	at net.minecraft.server.dedicated.DedicatedServer.func_71197_b(DedicatedServer.java:266)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:431)
	at java.lang.Thread.run(Thread.java:745)