Please go here and open a support ticket: http://support.x10hosting.com/ .
This is an issue that only an admin can fix. I had the same problem.
http://support.x10hosting.com/
Your FTP client should let you select all of the contents and drag it into the subdomain folder. Alternatively, you could set the directory of the subdomain to the existing folder.
What FTP client do you use?
In the past, it has taken them a day or two for me (a few hours if you're paid hosting). I'm sure they'll reply soon, just be patient. :)
Good luck with your site!
I feel really stupid now for not noticing that. However, this would still be a good implantation for the existing system and for minors, because it's against Paypal's terms to have a Paypal account if you're under the age of 18.
I can see how x10 cannot pay members for referring others, but it would be a cool idea if you got forum credits for getting other people to sign up for x10.
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