ok thank you. I thought that because the mime type is already enabled in the functions.php that it would be ok …. but I will definitely check this out. thank you.
Oh my gosh, this did the trick!! thank you so much!!
Wow, I had not even run across these before!! They might be just the ticket. Thank you so much!!
Well, it may be that I just needed to give things a bit of time — because now the sitemap is being displayed and all is working well.