how to start device on cisco modeling labs ?

[NamNguyen]

I had problems with cisco modeling labs(cml) with the following error:

(INFO) [Jun/18/2019 07:56:01] simulation "topology5-VdINyW": nodes can start
(ERROR) [Jun/18/2019 07:56:08] Failed to deploy node "~mgmt-lxc": Failed to create LXC "</Test/endpoint>-<topology5-VdINyW>-<~mgmt-lxc>"
(INFO) [Jun/18/2019 07:56:08] Starting node "iosv-1"
(INFO) [Jun/18/2019 07:56:14] Starting node "iosv-2"
(INFO) [Jun/18/2019 07:56:19] Node "iosv-1" state changed from ABSENT to ACTIVE
(INFO) [Jun/18/2019 07:56:19] Node "iosv-2" state changed from ABSENT to BUILDING
(INFO) [Jun/18/2019 07:56:38] Node "iosv-2" state changed from BUILDING to ACTIVE

plz help me !

[PeterGr]

Any idea where we can get some kind of training documentation on how to use CML? Can't figure out how to access devices to apply a config, or start them.