We check this website, now cst-c.com.cn is up and dont blocked for our system and other users of the Internet.
So, answer to question: Is cst-c Down Right Now? - NO! cst-c is up!
If you have problem with access to site cst-c, and domain cst-c.com.cn is not avalible.
Clear browser cache and/or try other web browser
(Chrome, Firefox or Safari).