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Re: the "core burn" I have had this happen before with low and slow cooks. I now light 3 spots at the periphery of the lump pile, with a weedburner. The problem has not recurred since I started doing this. If I'm grilling at higher temps for a shorter period, lighting one spot in the middle works well.
Smoked a 14lb ham overnight this past weekend, and went off without a hitch.
Another thing to consider also is that a large amount of meat like that likely "sweats" a lot of drippings, and can kill the fire. I usually use a drip pan (with an air gap underneath), especially when cooking large amounts of meat.