Hi Ildici,
In 18 trips to Jamaica staying at both a/i resorts (including Couples Negril) and smaller hotels, we have never come across a place that completely bans smoking. Some resort restaurants have separate "smoking" and "non-smoking" sections, but that's about it. As for Couples resorts, I can only tell you that their reservations only restaurant at CN WAS non-smoking, so I'm guessing that whichever restaurant is the gourmet place at COR, it, too, will likely be non-smoking.
Bars on the resort property....not a problem.
Happy Travels!