Hi @triciabishop is this for getting the taxonomy and post type associated in general? or is this more regarding the frontend display?
Asking because checking these two, which should be the first two listed, would handle the default “category” and “post_tag” taxonomies that show for blog posts for example.

However, display of them on the frontend may be a different story where templates may need to be edited.
Alternatively, are you perhaps asking about how to get the posts to show in the category and/or tag archives? say mysite.com/tag/some-tag ?
Thanks, Michael. This is a terrific plugin. That’s what I needed to know–I hadn’t added support for tags.
Cheers and have a great day!
Actually…I did not get the effect I expected. I expected a way to relate the tags hierarchically. How do I relate ‘Topics’ (=tags for this post type) to the sports category? Ex: For the baseball category I need a shinguard tag.
We don’t have any functionality to cross relate terms between taxonomies. For example a “topics” term from the “post_tag” taxonomy to a “sports” term from the “category” taxonomy.
If you’re referring to just parent/child relationships, like you have with that “category” taxonomy, we don’t have a way to change “post_tag” to behave that same way. However you could create your own taxonomy to be hierarchical with parent/child terms, that would behave similarly to categories.
Thanks, Michael. I’m only concerned about the backend UI of my custom post type. Guessing the answer is to use the regular WP tag interface for adding tags, regardless of the post type? Maybe they don’t need to be relational.
The front end display will be governed by the Document Library Pro plugin.
My goal is to display a Topics metabox for my PT which functions exactly like the WP tags metabox, except is labeled ‘Topics.’ I have created the metaboxes for my CPT categories (the CPTUI plugin created them as a result of my adding custom taxonomies). Category metaboxes have checkboxes. Tag metaboxes have a text input field. So, when I create a Topics taxonomy in the CPT plugin, I get a category metabox, not a tags metabox. I hope this makes sense.
The more I read over everything, the more it’s sounding like you created a custom taxonomy, that I believe you want to behave like categories, with the checkboxes, as opposed to behaving like tags, with the text input and auto-suggest. As is, it sounds like you named it “Topics”.
If that’s the case, then to get the checkboxes, you just need to set the “Hierarchical” setting to true for this custom taxonomy, and WordPress should take care of the rest of your.
Whew! That’s the solution! Thank you so much for your time. Cheers, Michael!