Will it be moral to continue working for a cigarette company knowing the sickenesses that smoking creates?

No I don't think it would be moral- and yet it would also seem immoral to me, as someone with a good job, to morally condemn someone who was working for a tobacco company because it was the only decent job that he could find to take care of his family. So I would go for degrees of culpability, but yes I would have to say that being part of a business that killed millions would not exactly be a righteous line of work.