The answer your husband get from CIC is that if you come to Canada as a fiancee, you need to get married within 90 days and mail the marriage certificate to CIC within 180 day. If you get marrried in China, just have your Chinese marriage certificate translated and notarized in notary office. I think you need 2 copies at least, one to mail to the Visa office with your application form, one to mail it to CIC when you arrive here.
Disclaimer: This is my personal interpretation.