If it works in your browser, it should work in nzb360. How are you entering in the details? Don't include http.

That's what I cant understand i literally have the following hostname.ddns.net

I know my API key is fine and also the port, because as soon as i change the Host address to the IP address all works fine.

if anyone is willing to provide a tutorial with more pictures, or maybe a video, I'm still confused with the explanation given, thank you

Do you have a base url setup for either of these?

Ex.
Hostname.ddns.net:8080/sabnzbd

if your on an Asus Router like myself RT-AC68U these two items helped me set up mine,

(Step 2) setup of DDNS for no-ip.com


(Step 3) video for manually assigning an ip address

http://www.youtube.com/watch?v=Osl_RQIzzIA