Well i thought you want information to enter .I mean DNS records. And if you cannot enter any entries (stuck at this screen ) then you should have asked co.cc admins and not X10?????
You can login to Cpanel and use File Manager to Upload files.OR Use FTP to upload.
Also Read this
http://x10hosting.com/forums/free-hosting/114005-important-information-must-read-before-posting.html