Spray an 8-inch springform pan with nonstick spray and set it aside.
In a medium bowl, whisk together the flour, cinnamon, baking powder, baking soda, and salt until well blended. Set aside.
In a large bowl beat the eggs with an electric mixer on high speed until thickened, about 2 minutes. Gradually add the sugar, beating until light and fluffy, about 3 minutes.
Reduce the speed to low. Beat in the apple butter and oil just until blended.
Add the flour mixture and beat just until blended.
Stir in the pineapple, carrots, raisins and walnuts until well combined.
Scrape the batter into the prepared pan.
Bake until a toothpick inserted in the center comes out clean, 35 to 40 minutes.
Remove from the oven and place on a rack to cool for 10 minutes. Release the springform pan and place the cake on a rack to completely cool.
To make the frosting, in a medium bowl, with an electric mixer on high speed beat together the cream cheese, confectioner sugar, yogurt and vanilla until smooth, about 1 minute. Place in the fridge until ready to frost the cake.
Place the cake on a serving plate. With a narrow metal spatula, coat the top of the cake evening with the frosting. Sprinkle the walnuts on top of the cake, if desired.
Cut into 16 even wedges.
The recipe calls for 1/2 cup apple butter, which adds sweetness, spice and moisture. Though I haven't tried it yet, I think applesauce would be a fine substitute.Weight Watchers PointsPlus: *5Weight Watchers Freestyle SmartPoints: *8