Cut the marshmallows in halves using scissors, and place in a large bowl. Toss with the digestive biscuits and candied cherries. Gradually stir in the sweetened condensed milk until the mixture becomes a soft, moist dough. It should not be too dry, so you may need to add a bit more of the milk.
Spread a generous layer of coconut out on a clean surface, and place the dough on top of it. Use your hands to form the dough into a long thick sausage, making sure it is well coated with coconut. Wrap in a double layer of plastic wrap, and refrigerate for 2 to 3 hours.
Unwrap the long piece of dough, and cut into slices to serve.
