Centreon Prometheus Kubernetes Api, is it paid or can work free of charge ?

Hello, 
I have not applied for any sub / paid service for centreon, in curious, is it possible to use the kubernetes monitoring without paying for it the stuff in the monitoring connectors menu I belive ? 

I tried the script on my centreon, looks promising : 
 

[root@ip-10-0-13-110 certs]# /usr/lib/centreon/plugins/centreon_prometheus_kubernetes_api.pl --plugin=cloud::prometheus::direct::kubernetes::plugin --mode=node-status --hostname=kube-prometheus.test.internal.com --url-path='/api/v1' --port='' --proto='https' --node='node=~".*"' --warning-status='' --critical-status='%{status} !~ /Ready/ || %{schedulable} =~ /false/' --warning-allocated-pods='' --critical-allocated-pods='' --units=''
OK: All nodes status are ok

Did it by this guide : 
 

in menu , I cannot install it :
 

Pressing subscription just leads to : “The Store is getting a makeover”.

Does this doable a free way ? What am I really missing there, a command and a template , right ? Are those available anywhere, any community collection ? Checked the github but no luck yet.  ​​​​​​​