Dissolve yeast and 1 teaspoon sugar in lukewarm water; stir well. Let stand 5 minutes or until bubbly.
Combine boiling water, shortening, remaining sugar, and salt in a large mixing bowl. Stir in 2 cups flour and egg, beating well. Stir in yeast mixture, and add enough remaining flour to make a soft dough. Turn dough out onto a floured surface, and knead 8 minutes or until smooth and elastic.
Place dough in a greased bowl, turning to grease top. Cover and let rise in a warm place (85°), free from drafts, 1 hour or until doubled in bulk.
Punch dough down, and let rest 5 minutes. Divide dough in half. Roll each half into an 18- x 10-inch rectangle on a lightly floured surface. Spread 1 cup orange marmalade over each dough rectangle, leaving a 1/2- inch margin. Roll up jellyroll fashion, starting at long side. Cut roll into 1-inch slices. Place slices, cut side down, in greased muffin pans.
Cover and repeat rising procedure 45 minutes or until doubled in bulk. Bake at 375° for 15 minutes or until rolls are browned. Remove rolls from pans immediately. Pour glaze over warm rolls, and serve.