Cannot configure timer with addon variable from rogro82

Hi

I’m trying to create a timer using the “variable” addon. I tried the example provided, but I keep getting the following error.

2019-10-06 10:40:47 INFO (MainThread) [homeassistant.helpers.script] Script timer start sous-sol: Running script
2019-10-06 10:40:47 INFO (MainThread) [homeassistant.helpers.script] Script timer start sous-sol: Executing step call service
2019-10-06 10:40:47 INFO (MainThread) [homeassistant.helpers.script] Script timer start sous-sol: Executing step call service
2019-10-06 10:40:48 ERROR (MainThread) [homeassistant.core] Error doing job: Exception in callback async_track_utc_time_change.<locals>.pattern_time_change_listener(<Event time_c....002316-04:00>) at /usr/src/homeassistant/homeassistant/helpers/event.py:402
Traceback (most recent call last):
  File "/usr/local/lib/python3.7/asyncio/events.py", line 88, in _run
    self._context.run(self._callback, *self._args)
  File "/usr/src/homeassistant/homeassistant/helpers/event.py", line 411, in pattern_time_change_listener
    calculate_next(now)
  File "/usr/src/homeassistant/homeassistant/helpers/event.py", line 395, in calculate_next
    localized_now, matching_seconds, matching_minutes, matching_hours
  File "/usr/src/homeassistant/homeassistant/util/dt.py", line 256, in find_next_time_expression_time
    raise ValueError("Cannot find a next time: Time expression never " "matches!")
ValueError: Cannot find a next time: Time expression never matches!

Most likely it is a bad configuration on my side, but I can’t really see my error

I was wondering if anyone would have a thought about my problem.
I’m running hass.io on ubuntu.
Home assistant version is 0.99.3
variable addon commit version is fd9b44e

Here’s the relevant code

[variable]
  timer_soussol:
    value: 30
    attributes:
      icon: mdi:alarm


[script]
'1570313908374':
  alias: timer start sous-sol
  sequence:
  - data:
      value: '30'
      variable: timer_soussol
    service: variable.set_variable
  - data:
      entity_id: automation.timer_countdown_sous_sol
    service: automation.turn_on

[automation]
- id: '1570314313861'
  alias: timer_countdown_sous_sol
  initial_state: 'off'
  trigger:
  - hours: ''
    minutes: ''
    platform: time_pattern
    seconds: /1
  condition: []
  action:
  - data:
      value_template: '{{ [((variable.state | int) - 1), 0] | max }}'
      variable: timer_soussol
    service: variable.set_variable


- id: '1570314576664'
  alias: timer_end_sous_sol
  trigger:
  - entity_id: variable.timer_soussol
    platform: state
    to: '0' 
  condition: []
  action:
  - data:
      entity_id: automation.timer_countdown_sous_sol

Thank in advance

Regards