Program: 109840
Project: 109840
Buggy source:
public void spawnLevelEntities(BuildJob buildJob){
  Build build=buildJob.build;
  World worldRef=FMLCommonHandler.instance().getMinecraftServerInstance().worldServerForDimension(build.dim);
  List ents=worldRef.loadedEntityList;
  for (int i=0; i < ents.size(); i++) {
    Entity ent=(Entity)ents.get(i);
    if (ent instanceof EntityItem) {
      ent.setDead();
    }
  }
  if (build.entities != null) {
    for (int var17=0; var17 < build.entities.tagCount(); ++var17) {
      NBTTagCompound var16=(NBTTagCompound)build.entities.getCompoundTagAt(var17);
      Entity var18=EntityList.createEntityFromNBT(var16,worldRef);
    }
  }
  if (build.tileEntities != null) {
    for (int var21=0; var21 < build.tileEntities.tagCount(); ++var21) {
      NBTTagCompound var20=(NBTTagCompound)build.tileEntities.getCompoundTagAt(var21);
      TileEntity var13=worldRef.getTileEntity(build.map_coord_minX + var20.getInteger("String_Node_Str"),buildJob.build_startY + var20.getInteger("String_Node_Str"),build.map_coord_minZ + var20.getInteger("String_Node_Str"));
      if (var13 instanceof SchematicData) {
        ((SchematicData)var13).readFromNBT(var20,build);
      }
 else       if (var13 != null) {
        var13.readFromNBT(var20);
      }
      if (buildJob.customGenCallback != null) {
        NBTTagCompound nbt=buildJob.customGenCallback.getInitNBTTileEntity();
        if (nbt != null) {
          if (var13 instanceof ITileEntityCustomGenData) {
            ((ITileEntityCustomGenData)var13).initWithNBT(nbt);
          }
        }
      }
      if (var13 != null) {
        var13.xCoord=build.map_coord_minX + var13.xCoord;
        var13.yCoord=buildJob.build_startY + var13.yCoord;
        var13.zCoord=build.map_coord_minZ + var13.zCoord;
        try {
          Packet packet=var13.getDescriptionPacket();
          if (packet != null) {
            MinecraftServer.getServer().getConfigurationManager().sendPacketToAllPlayers(packet);
          }
        }
 catch (        Exception ex) {
          ex.printStackTrace();
        }
      }
    }
  }
}

Fixed version (ground truth):
public void spawnLevelEntities(BuildJob buildJob){
  Build build=buildJob.build;
  World worldRef=FMLCommonHandler.instance().getMinecraftServerInstance().worldServerForDimension(build.dim);
  List ents=worldRef.loadedEntityList;
  for (int i=0; i < ents.size(); i++) {
    Entity ent=(Entity)ents.get(i);
    if (ent instanceof EntityItem) {
      ent.setDead();
    }
  }
  if (build.entities != null) {
    for (int var17=0; var17 < build.entities.tagCount(); ++var17) {
      NBTTagCompound var16=(NBTTagCompound)build.entities.getCompoundTagAt(var17);
      Entity var18=EntityList.createEntityFromNBT(var16,worldRef);
    }
  }
  if (build.tileEntities != null) {
    for (int var21=0; var21 < build.tileEntities.tagCount(); ++var21) {
      NBTTagCompound var20=(NBTTagCompound)build.tileEntities.getCompoundTagAt(var21);
      TileEntity var13=worldRef.getTileEntity(new BlockPos(build.map_coord_minX + var20.getInteger("String_Node_Str"),buildJob.build_startY + var20.getInteger("String_Node_Str"),build.map_coord_minZ + var20.getInteger("String_Node_Str")));
      if (var13 instanceof SchematicData) {
        ((SchematicData)var13).readFromNBT(var20,build);
      }
 else       if (var13 != null) {
        var13.readFromNBT(var20);
      }
      if (buildJob.customGenCallback != null) {
        NBTTagCompound nbt=buildJob.customGenCallback.getInitNBTTileEntity();
        if (nbt != null) {
          if (var13 instanceof ITileEntityCustomGenData) {
            ((ITileEntityCustomGenData)var13).initWithNBT(nbt);
          }
        }
      }
      if (var13 != null) {
        var13.setPos(new BlockPos(build.map_coord_minX + var13.getPos().getX(),buildJob.build_startY + var13.getPos().getY(),build.map_coord_minZ + var13.getPos().getZ()));
        try {
          Packet packet=var13.getUpdatePacket();
          if (packet != null) {
            FMLCommonHandler.instance().getMinecraftServerInstance().getPlayerList().sendPacketToAllPlayers(packet);
          }
        }
 catch (        Exception ex) {
          ex.printStackTrace();
        }
      }
    }
  }
}