Two 'style' questions.... lamb and couscous

I am cooking a leg of lamb on Sat. and want to know if anyone has cooked one and then finished it off in a BBQ (gas)? I like to put fresh rosemary on the fire and let the smoke flavor the meat...but have only tried it with smaller cuts of meat.

Also...I am making Couscous wth it...and since the chard recipe has garlic, raisins, cumin,pinenuts, etc., I want the Couscous to be slightly blander but still interesting. Any suggestions?

TIA
Carol