Tutorial omits lots of stuff, you're probably hanging on some password prompt. You also might have hit limit for downloading containers from dockerhub, it might take a while to have it reset.
Other solution might be to use --edge version, but this openstack is in a such a rapid development cycle that i'm getting lost as to what's stable and what's not.
I have this little helper script (running it with sudo) for setting up the openstack/ubuntu user:
#!/bin/bash
set -e
apt install whois #for mkpasswd
USERNAME=ostack
PASSHASH=`mkpasswd -m sha-512 $USERNAME`
useradd -m -p $PASSHASH -s /bin/bash $USERNAME
echo "$USERNAME ALL=(ALL) NOPASSWD: ALL" > /etc/sudoers.d/91-$USERNAME
runuser -l $USERNAME -c 'ssh-keygen -t rsa -q -f "$HOME/.ssh/id_rsa" -N ""'
cat /home/$USERNAME/.ssh/id_rsa.pub > /home/$USERNAME/.ssh/authorized_keys
chown ostack:ostack /home/$USERNAME/.ssh/authorized_keys
chmod 700 /home/$USERNAME/.ssh
chmod 600 /home/$USERNAME/.ssh/authorized_keys
# Do this manually for the node you're on as $USER
# This is for proper entry in known_hosts
#ssh YOUR_REAL_FQDN.COM
I also have my little LiveStreams on YT where i tackle this stuff:
LINK