I got your system up and running.

You need to update your tutorial to tell people to auto start their docker. After the system reboots all DynDNS resolution borked and I was scratching my head as to why.

From the command prompt:
docker update --restart unless-stopped dyndns

I also hate how I have to modify the /etc/systemd/resolved.conf > flip =no <-- to "yes" > reboot > apt update && apt upgrade -y <-- so my system can resolve DNS and update > go back into the file and flip it to "yes" > reboot again.

^^^^ is that necessary? It's terrible! We need a fix please! :-)

Thanks!