many questions, I hope I can help, so let's go...
You may put your devices with static IPs in the "Hosts" list, so they can be found by their name.
You may put alias names for your Nethserver in the "server alias" list so users may reach it by easytomemorize.myhome.lan.
Nothing, this is already done by your registrar as you wrote. You can check it on NS
or here: http://network-tools.com/nslook/. Just enter your domain and you should find your IP in the result.
It depends...if you want that neth01.myplace.com is seperately reachable, you may do it. You maybe want www.myplace.com pointing to server A and mail.myplace.com pointing to server B and so on. I assume for your home server it's enough to let myplace.com point to your public IP.
The firewall is well optimized after installing. If you don't have a special configuration or special devices, just enable it.
No, green to red is allowed by default.
Firewall policies allow inter-zone traffic accordingly to this schema:
GREEN -> BLUE -> ORANGE -> RED
What should work on myplace.com? You may host a website on NS. Then you won't need a firewall configuration, because httpd(web server) is allowed by default.
Please explain what was hard to understand because we want the docs to be useful and understandable. If you have ideas to improve the docs feel free to share them...
Greetings from Vienna, Austria.