Combine melted margarine and the yogurt in a mixing bowl.
Beat to blend.
Beat in sugar replacement and fructose.
Add eggs, one at a time, beating well after each addition.
Beat in vanilla.
Stir in flour, baking soda, and salt.
Fold in currants.
Cover and chill at least 2 hours.
Flour your hands, and shape dough into balls; then flatten balls slightly in the palm of your hand.
Place on lightly greased cookie sheets.
Bake at 350°F (175°C) for 8 to 9 minutes.
Move to cooling racks.