Well I went to my Linksys admin panel and added a Nicecast port range, 8000 to 8100 (picture 1), as the instructions told me to do.
Then, I went to the Firewall section of the System Preferences and opened port 8000 (Pictures 2 and 3), as the instructions told me to do.
The instructions then say that's all I need to do and it should work...but it's not.... 😕