OK, lesson learned. After direct grilling of the fatty lamb ribs, they dripped so much grease onto my charcoal, that I've been having issues with both temperature control and lots of smoke production in subsequent cooks. Next time, I'll put just enough charcoal in the basket to do the ribs and not fill it up, like normal.
Here's a pic of tonight's cook (Jerk Chicken thighs). Every time that I opened the lid to flip the chicken, this happened!
The good news - it didn't impact the flavor of the chicken. Yes, there's a plated picture - chicken with Jamaican curry rice and a nice side salad. The wine was a very nice Viognier that I picked up at Trader Joe's last week.