costmap_2d: how to publish local costmap to topic

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I'm running costmap_2d with PointCloud2 feed from a 3D lidar as the only source. Lidar points are preliminary filtered, the ground is mostly segmented out. It is used as a singular source for the singular plugin of type ObstacleLayer.

As I'm using the output occupancy grid for use with home-made custom code, I would like to have a small portion of costmap near the robot position be published after every update as OccupancyGrid. I guess this is what local_costmap settings can be used for, right?

Well, false. The setup works the same way with and without additional YAML file for the local costmap. Even worse, I cannot get the full costmap to be published every step. The /costmap/costmap topic is being published once at the start, all the rest time only costmap/costmap_update are published. This is happening despite always_send_full_costmap: true in the config.

What and where should I write to get instant local occupancy grid published?

Below are my two YAML files and the portion in the launchfile where I run the costmapping node. I'm working in Xubuntu 16.04, ROS Kinetic.

in the launchfile:

<node name="costmap_node" pkg="costmap_2d" type="costmap_2d_node" output="screen" clear_params="true">
      <rosparam file="$(find lidar_proc)/params/costmap/costmap_common_voxel_params.yaml" command="load" ns="costmap" />
<rosparam file="$(find lidar_proc)/params/costmap/local_costmap_quan_params.yaml" command="load" ns="costmap" />
          <remap from="/cloud_in" to="/lidar/flt_out_cloud"/>
    </node>

costmap_common_voxel_params.yaml:

transform_tolerance: 0.5,
robot_base_frame: base_link,

width: 200,
height: 200,
origin_x: -150,
origin_y: -50,

resolution: 0.2,
footprint:
- [-11.2, -3.2]
- [-11.2, 3.2]
- [0.2, 3.2]
- [0.2, -3.2],
update_frequency: 10.0,
static_map: false,
publish_frequency: 10.0,
max_obstacle_height:  3.0,
min_obstacle_height:  -2, 
obstacle_range: 70.0,
raytrace_range: 70.0,
always_send_full_costmap: true,

plugins:
    - {name: obstacles,          type: "costmap_2d::VoxelLayer"}

obstacles: {
  z_resolution: 0.2,
  z_voxels: 15,
  origin_z: -2.0,
  publish_voxel_map: true,
  mark_threshold: 0.5,
  enabled: true,
  max_obstacle_height:  3.0,
  min_obstacle_height:  -2,
  obstacle_range: 70.0,
  raytrace_range: 70.0,
  inflation_radius: 0.0,
  combination_method: 1,
  observation_sources: lidar_obstacles,
  lidar_obstacles: {
       sensor_frame: /Sensor,
       data_type: PointCloud2,
       topic: /cloud_in,
       expected_update_rate: 5.0,
       observation_persistence: 0.0,
       max_obstacle_height:  3.0,
       min_obstacle_height:  -2,
       marking: true,
       clearing: false,
       raytrace_range: 70.0,
       obstacle_range: 70.0}
  }

local_costmap_quan_params.yaml:

local_costmap:
  global_frame: /map
  robot_base_frame: /base_link
  static_map: false
  rolling_window: true
  resolution: 0.2
  transform_tolerance: 0.5
  width: 20
  height: 20
  always_send_full_costmap: true,
  plugins:
    - {name: obstacles,      type: "costmap_2d::ObstacleLayer"}