Lightly brown the pork roast on the stove top, just a minute or so on each side.
Spray the inside of the slow cooker with non-stick spray. Place the cubed potatoes in the bottom.
Place the browned roast in the slow cooker, on top of the cubed potatoes.
Put the cranberry sauce, the canned & dried apricots, & the diced onion in a large bowl, & use a potato masher to blend them together into what will end up looking sort-of like a "relish".
In a small bowl to the side, combine the sugar & other seasonings. I like to do this separately, because the ground mustard has a tendency to clump. Once these are mixed thoroughly, sprinkle them over your mashed-up "relish", & use the potato masher again to make sure it's well distributed.
Pour the mixture over the roast & potatoes, & cover. Cook on "low" setting for 5-6 hours, or until the roast has cooked through. Cooking time may vary, depending on your slow cooker.