To prepare the dough: In the bowl of a standing electric mixer fitted with a dough hook, dissolve the yeast in 1/4 cup of the warm water. Sprinkle in 1/4 teaspoon of the sugar and let stand until foamy, about 10 minutes.
Turn the mixer on low speed and add the remaining water, sugar, melted margarine, eggs, and salt. Add 2 cups of the flour and turn the speed up to medium; continue to mix until incorporated. Gradually add the remaining flour, and continue to mix until the dough holds together and pulls away from the sides of the bowl; the dough will be very soft.
Knead the dough on a lightly floured surface, until smooth and elastic. Rub the inside of a mixing bowl with the oil and put the dough in it, turning to coat. Cover with a towel or plastic wrap and let rise at room temperature for about 1 1/2 hours, until doubled in size.
To prepare the filling: Combine the brown sugar and cinnamon in a mixing bowl. Add the orange zest, raisins, walnuts, and melted margarine. Fold the ingredients together to combine.
Preheat the oven to 325 degrees F.
Line a sheet pan with parchment paper and brush with melted margarine.
Roll the dough out on a lightly floured surface into a large rectangle, about 10 by 18-inches. Brush the surface of the dough with melted margarine and spread the filling evenly across. Roll the dough up, jelly roll-style, into a long cylinder, and twist it a few times like your wringing out a towel. Put the dough on the sheet pan and coil it around like a pinwheel, tuck the loose end of the dough under so it doesn't unravel. Brush the top of the dough with more melted margarine. Bake for 45 minutes to 1 hour until your kitchen smells like cinnamon, and the babka is golden brown. Cool in the pan for 5 minutes, and then transfer to a wire rack.
To prepare the orange glaze: Mix the all the ingredients together in a bowl, until the sugar dissolves. Whisk the glaze to smooth out any lumps; drizzle it over the top of the babka while it is still warm.