Lxc on Arch linux - error main: 260 No container config specified

Hi
I am trying to create lxc ubuntu container or Arch
I have a feeling I am missing something.
I done all the set up of etc/subuid and subgid and added them to ~/.config/lxc/defoult.config
I done the
$systemd-run --unit=myunit --user --scope -p "Delegate=yes" -- lxc-start myFirstContainer

and I get

lxc-start: myFirstContainer: tools/lxc_start.c: main: 266 No container config specified

in the checkconfig few line have red next to them

Cgroup v1 systemd controller: missing
Cgroup v1 freezer controller: missing

and few in orange/brown

CONFIG_NF_NAT_IPV4: missing
CONFIG_NF_NAT_IPV6: missing

so I am not sure what next?
Any advise will be greatfully accepted.
Thanks

p.s
I was not clear from the documentation what unit=my-unit is doing nor what should I replace the my-unit with
thank you again

Hi

~/.config/lxc/defoult.config

Did you mean ~/.config/lxc/default.config ?

On my system I found that I needed to configure a systemd drop-in file for the user

sudo systemctl edit user@1000.service
### Anything between here and the comment below will become the new contents of the file

[Service]
Delegate=yes

### Lines below this comment will be discarded

Save this file then reboot your system.

Check

cat /sys/fs/cgroup/user.slice/user-1000.slice/cgroup.controllers 

returns

cpuset cpu io memory pids 

See the Arch Wiki notes on User delegation.

Now this is set up I can create and start using the lxc-create, lxc-start without having to embed in a systemd-run command.

I have also found that lxc-create, lxc-start run without embedding them in a systemd-run command if I launch them in Gnome Terminal. Otherwise this is required.

(pacman -Q lxc = lxc 1:4.0.12-1)

I appreciate your help.
I put the Arch on hold at the moment as I’m getting to grips with lxc on debian and Ubuntu.
Once I feel more confident with these Distros I’ll be back with Arch and no doubt your advice will come in handy.

Thanks again for your help.