According to the queen of dehydrating Deana DeLong, she says cranberries do best when they're soaked in a sugar solution (glace) over a period of a few days. If not soaked, dip in boiling water to crack the skins. Dry at 130-140 degrees until dry. They should be shriveled with no sign of moisture. Sugared cranberries should be leathery and a little sticky. She doesn't say how long this should take but from my experience this all depends on yur dehydrator and the humidity when drying. Some of my drying has taken far longer than she said it would.