Your main domain name must remain an x10 supplied one.
You can add your TLD to the account two ways.
Add-on. Separate from your main domain. You now have two sites.
Parked. Same content as your main domain. Just called by another name. Set up properly nobody will know that myfrenchpastry.com is the same as bonbon.x10host.com
Thanks I read that. But I thought that I also saw somewhere that you could get your main domain changed to a TLD. And that you use to be able to do it but people thought that you would get the domain for free on the signup page so that's why they only have the subdomains.