Patrick, thank you for your help and patience.
I successfully installed WordPress some days ago in my main domain folder. Everything appears to be there. As I don't yet know what to do with it, I don't know that it works, but assume so.
Per your suggestion, I added a subdomain. Using easy mode to install WP, I changed the default to the name of the subdomain. I received an error message that the subdomain already existed and I must pick another one.
I did, creating a sub subdomain, and completed the install. This sub subdomain never appeared in my domain list (and yes, I did check to make sure it wasn't hidden) not was it visible via ftp. I did receive the email, yes.
It does take time to propagate, you're right. Maybe I wasn't sufficiently patient.
It's entirely possible that my own flesh-and-blood CPU has been adversely affected by the heat we've been having. With a somewhat cooler brain this morning, I will try again.