Check out the config template file. You may provide it when asked during ./jlmkr.py create or, if you have the template file stored on your NAS, you may provide it directly by running ./jlmkr.py create --start --config /mnt/tank/path/to/docker/config mydockerjail. If you want the nvidia-container-toolkit to be installed, ensure you set gpu_passthrough_nvidia=1 when creating the jail.