Hello Jan,
I'm not sure why but whenever I set my Web Server Port to a port other than 80, lets say 8000 for example, I cannot access the setup page via my browser on my LAN. It keeps saying "page not found" When I tried changing the port, I set it in the Microbit Setup Manager and I forwarded the same port in my internet gateway. The unit worked fine, but I could not access the setup page. When I put the port back to 80, I can access the setup page without any issues.
Also, maybe this is part of the same problem, but I cannot access the setup page from outside of my LAN. I can see my ddns status, but I cannot get to my Hostname.ddns.remoterig.com page. It also says "page not found".
Dale