If you set up the extra domain using x10hostings name servers you shouldn't need to do anything, if you used a record and your servers shared IP you probably is gonna need to change that once it is all done since they will get new IPs.
if you check the news section you'll see that there's a bit of work going in with all free servers, ny guess is that is why you can't reach it right now. Link: http://forums.x10hosting.com/news-announcements/98132-update.html
The staff are working with the servers, there's more info here: http://forums.x10hosting.com/news-announcements/98132-update.html
I suspect that has to do with your problems
if you run into any problems just ask :) If you use irc there's a lot helpful people there
server: irc.x10hosting.com
channel: #x10hosting
Irc is not official support, but for the most time there's someone there that can assist
at co.cc you should be able to configure the name servers. You need to use ns1.x10hosting.com and ns2.x10hosting.com (putting your servers shared IP as a cname works, but name servers are the prefered option)
The co.cc domain needs to be either parked, addon or set as main domain with...
or maybe a sign of someone that haven't really done much posting until recently.... For the most part of the time I've been a member I've been rather quiet here in the forums
for the rss in comments, find this: #extrastuff a {color:#222; font-size:0.8em;} edit the color:#222; part.
for the post titles, find this line: .topPost h2.topTitle a { edit the color:#fff; in that class.