When you go to your FTP server. and then go to your themes folder/directory, is the c3s folder in there? and in the c3s folder/directory is there a styles, forums and images folder and then some 6 or so "other" files? Like header.html, theme.php etc.?

If you're completely lost, PM me your FTP info and your Admin loggin and website addy and I'll fix it for you. I'm feeling a little generous. I'll even tell you what was wrong.