Cannot do entities configuration


I have just configured my Echo device to work with Home Assistant and all my devices are correctly discovered, but I am not able to customize them (name, filtering out some devices).

This ispart of my conig.yml:

   >      cloud:
>           alexa:
>             filter:
>               include_entities:
>                 - climate.danfoss_z_thermostat_014g0013_heating_1
>                 - media_player.denon_avrx400
>               exclude_entities:
>                 - climate.danfoss_z_thermostat_014g0013_heating_1_2
>             entity_config:
>               media_player.denon_avrx4000:
>                 name: denon
>                 description: Denon in livingroom
>                 display_category: SWITCH
>               climate.danfoss_z_thermostat_014g0013_heating_1:
>                 name: kitchen thermostat
>                 description: Thermostat in the kitchen
>                 display_category: THERMOSTAT

Whatever I do in the config, it looks like it makes no impact on Alexa Smart Home skills. Devices are still being discovered under their original names.

Anybody had the same problem?

This is what I can see in the logs, when doing device discovery on Alexa App:

2018-08-30 23:31:30 INFO (MainThread) [homeassistant.core] Bus:Handling <Event alexa_smart_home[L]: request=namespace=Alexa.Discovery, name=Discover, response=namespace=Alexa.Discovery, name=Discover.Response>
2018-08-30 23:31:46 ERROR (MainThread) [] Error handling message
Traceback (most recent call last):
  File "/usr/local/lib/python3.6/site-packages/homeassistant/components/cloud/", line 167, in _handle_connection
    hass,, msg['handler'], msg['payload'])
  File "/usr/local/lib/python3.6/site-packages/homeassistant/components/cloud/", line 223, in async_handle_message
    return (yield from handler(hass, cloud, payload))
  File "/usr/local/lib/python3.6/site-packages/homeassistant/components/cloud/", line 231, in async_handle_alexa
    hass, cloud.alexa_config, payload)
  File "/usr/local/lib/python3.6/site-packages/homeassistant/components/alexa/", line 732, in async_handle_message
    response = await funct_ref(hass, config, request, context)
  File "/usr/local/lib/python3.6/site-packages/homeassistant/components/alexa/", line 874, in async_api_entity_wrapper
    return await funct(hass, config, request, context, entity)
  File "/usr/local/lib/python3.6/site-packages/homeassistant/components/alexa/", line 1525, in async_api_reportstate
  File "/usr/local/lib/python3.6/site-packages/homeassistant/components/alexa/", line 277, in serialize_properties
    prop_value = self.get_property(prop_name)
  File "/usr/local/lib/python3.6/site-packages/homeassistant/components/alexa/", line 413, in get_property
    'value': float(temp),
TypeError: float() argument must be a string or a number, not 'NoneType'