Domain

I want to use blog.[website].com (amongst other subdomains), whilst keeping my apex domain linked to Blot. I've tried doing this, and I've updated the CNAME records to reflect this, but when I go to my subdomain website I get this message: "Your domain is almost set up. You have successfully pointed your domain to Blot’s server. The DNS records you created are working. You still need to enter your domain on the dashboard. Blot must know which site to show here. Please update the domain settings page on your site’s dashboard." My normal website with the apex domain works fine.

Is it possible to add a folder of documents that become a sub-domain to my main site. e.g. newfolder/mydomain.com?