Program: 27576
Project: 27576
Buggy source:
/** 
 * @author Zidane - June 2nd, 2016
 * @reason Forge's initDimension is very different from Sponge's multi-world. We basically rig it into our system so mods work.
 * @param dim The dimension to load
 */
@Overwrite public static void initDimension(int dim){
  if (WorldManager.getWorldByDimensionId(dim).isPresent()) {
    return;
  }
  if (dim == 0) {
    throw new RuntimeException("String_Node_Str");
  }
  final WorldServer worldServer=WorldManager.getWorldByDimensionId(0).orElseThrow(() -> new RuntimeException("String_Node_Str" + "String_Node_Str"));
  final DimensionType dimensionType=WorldManager.getDimensionType(dim).orElseThrow(() -> new RuntimeException("String_Node_Str" + "String_Node_Str"));
  final WorldProvider provider=dimensionType.createDimension();
  WorldProperties properties=WorldManager.getWorldProperties(provider.getSaveFolder()).orElse(null);
  final AnvilSaveHandler saveHandler=new AnvilSaveHandler(getCurrentSaveRootDirectory(),provider.getSaveFolder(),true,SpongeImpl.getServer().getDataFixer());
  if (properties == null) {
    final WorldInfo info=saveHandler.loadWorldInfo();
    final IMixinWorldInfo mixinWorldInfo=(IMixinWorldInfo)info;
    ((IMixinWorldInfo)info).createWorldConfig();
    mixinWorldInfo.setDimensionType((org.spongepowered.api.world.DimensionType)(Object)dimensionType);
    mixinWorldInfo.setDimensionId(dim);
    ((WorldProperties)mixinWorldInfo).setKeepSpawnLoaded(dimensionType.shouldLoadSpawn());
    mixinWorldInfo.getWorldConfig().save();
    WorldManager.setUuidOnProperties(WorldManager.getCurrentSavesDirectory().get(),((WorldProperties)info));
    properties=(WorldProperties)mixinWorldInfo;
    WorldManager.registerWorldProperties(((WorldProperties)mixinWorldInfo));
  }
  final WorldServerMulti worldServerMulti=new WorldServerMulti(SpongeImpl.getServer(),new WorldServerMultiAdapterWorldInfo(saveHandler,(WorldInfo)properties),dim,worldServer,SpongeImpl.getServer().theProfiler);
  WorldManager.forceAddWorld(dim,worldServerMulti);
  Sponge.getEventManager().post(SpongeEventFactory.createLoadWorldEvent(Cause.of(NamedCause.source(SpongeImpl.getServer())),(World)worldServerMulti));
}

Fixed version (ground truth):
/** 
 * @author Zidane - June 2nd, 2016
 * @reason Forge's initDimension is very different from Sponge's multi-world. We basically rig it into our system so mods work.
 * @param dim The dimension to load
 */
@Overwrite public static void initDimension(int dim){
  if (WorldManager.getWorldByDimensionId(dim).isPresent()) {
    return;
  }
  if (dim == 0) {
    throw new RuntimeException("String_Node_Str");
  }
  WorldManager.getWorldByDimensionId(0).orElseThrow(() -> new RuntimeException("String_Node_Str" + "String_Node_Str"));
  final DimensionType dimensionType=WorldManager.getDimensionType(dim).orElseThrow(() -> new RuntimeException("String_Node_Str" + "String_Node_Str"));
  final WorldProvider provider=dimensionType.createDimension();
  provider.setDimension(dim);
  String worldFolder=provider.getSaveFolder();
  WorldProperties properties=WorldManager.getWorldProperties(worldFolder).orElse(null);
  if (properties == null) {
    final WorldArchetype.Builder builder=SpongeImpl.getRegistry().createBuilder(WorldArchetype.Builder.class).dimension((org.spongepowered.api.world.DimensionType)(Object)dimensionType).keepsSpawnLoaded(dimensionType.shouldLoadSpawn());
    String modId=SpongeMod.instance.getModIdFromClass(provider.getClass());
    final WorldArchetype archetype=builder.build(modId + "String_Node_Str" + dimensionType.getName().toLowerCase(),dimensionType.getName());
    properties=WorldManager.createWorldProperties(worldFolder,archetype);
    ((IMixinWorldInfo)properties).setDimensionId(dim);
  }
  Optional<WorldServer> optWorld=WorldManager.loadWorld(properties);
  if (!optWorld.isPresent()) {
    SpongeImpl.getLogger().error("String_Node_Str",properties.getWorldName());
  }
}