Chicken – Is it best to slice roast meat if eating the next day

Let it rest anyway. Even at low temperatures, the juices will be flowing through the meat. Resting stops this process.

As for the strange colour-changing meat, I suspect you just weren't observant. Meat that has gone brown will not spontaneously go pink again.

If it's been fully cured (smoked, then hung for a few months), it likely just needs to be warmed through for serving (or even just sliced).

If it's soft, you might need to cook it, and then you could roast it in the oven ... a crock pot might be okay; it's hard to say without having seen it.

But if it's quite firm, I'd likely just slice pieces off like you might other dry cured hams like Prosciutto, speck, jamón or country ham.

If it's heavily salted, I'd be more likely to use it as a flavoring than a meat -- cut off bits, and add to vegetable dishes when cooking. It goes great with dark greens or in bean dishes. (I just had an excellent bean & ham soup last night at a meeting that a few of us treat as a pot-luck)