Thanks for the clarification. So, I have gone back through the process, made the necessary php and css code changes and now I have what I need to create my category archive landing page. Thanks to everyone who contributed!
I still have a strange glitch on the category description section.
Here are some screen shots.
It is as if there is something going on in the "top section" only - something that has "stripped" the headings only. For example, if I bold the text, that works.
If you see the screen shots, you'll see that once I have gone further down in the page, that issue disappears.
Hopefully, this is not outside of the scope of support. If it is, I guess I can insert a big image or a lot of space before I start with my content.