Unfortunately, age difference is used as a determining factor. Morocco is a tough country with many young men trying to get into Canada by marrying Canadian women, no matter what their age. A 20 year age difference will be a HUGE red flag to the officials there, and based on that alone they could deem your marriage to be just a marriage of convenience and deny your husband's application. It happens all the time.
In my opinion, you really only have one choice, and that is to stay in Morocco with him as long as possible. You will have to prove way above and beyond the regular person that yours is a marriage of love, and not convenience. My suggestion would be to have loads of evidence, and not put your application in for a few months so that you can show that you are living together. Pictures, emails, phone bills, everything has to be submitted.
Are you muslim? If not, this will cause even more difficulty. Will you be having children with him? A young Morrocan muslim man marrying a much older non-muslim Canadian woman who will not be having his children will be a very hard story for the officials to swallow.
I'm sorry that this isn't good news, but it's best to know what you're up against. And I'm sorry for what I'm about to say, but I have to say it....are you sure it is not just a marriage of convenience? Moroccan men are known for marrying older women in Canada and the US and then leaving her when they arrive...going on to marry a woman from their community here in Canada. Search some of the stories here...they are kind and loving before the marriage, and then things change afterwards. I don't want you to get your heart broken.
However, every circumstance is different, and I would not like to stereotype an entire nation. So if you are 100% SURE that your marriage is genuine and you have seen no red flags in your relationship thus far, work your butt off preparing the best application possible and spend those 4 months in Morocco to further strenghten your case.
Laura
ps. one more thing just came to mind which makes me wonder...My husband and I are very much in love and cannot wait to be together, so if I had had the option to live with him for 4 months after our marriage I would have jumped at the chance! For the simple fact that you would easily return to Canada and not live with him when you have that option, it makes me a bit suspicious.