Thankyou, John. I do have canBeRoot implemented.
Perhaps I'm missing something obvious here? I am running Pier, and I'm in a blog, and I select Add. I get a dropdown menu named Type:.
I select Component and then click the Add button. I get another dropdown menu named Component Class:.
It has a long list of options but doesn't include the Seaside component that I want to embed and doesn't offer any other option that would lead me there. On Lawson's video it appears that he selects his component from this list but he says, "it's at the bottom where you can't see it."