Place waxed paper over one full and two half Threshold Arch Patterns. Using royal icing, pipe tip 1D band (smooth side up) over patterns. Let dry overnight. Turn over dried arch pieces and overpipe with tip 1D. Immediately overpipe tip 2 lattice. Let dry overnight. Turn arch pieces again; pipe tip 2 lattice. Let dry completely.
To assemble Threshold Arch: Using royal icing, secure pillars to plate; attach full arch piece between pillars. Attach nylon thread through filigree bells and hang over arch. Let dry overnight.
Using royal icing, make 135 tip 225 drop flowers with tip 2 dot centers; 75 tip 102 forget-me-nots with tip 3 centers; 40 tip 66 bluebells on 1 1/4 in. Lily Nail, with tip 3 centers and three stamens. Make extras to allow for breakage, let dry.
Bake and cool two 9 in. round cakes, 1 1/2 in. high, and 2-layer hexagon cake. Ice and prepare cakes for stacked construction.
On round cake: Using Cake Dividing Set, divide cake into 6ths; mark center of garland 1 3/4 in. down from top. Pipe tip 2 lattice in garland area. Pipe tip 16 top and tip 18 bottom shell borders. Edge plate with tip 16 c-motion shells.
On hexagon cake: Make ovals on side panels of cake. Pipe tip 1D band (smooth side up) around bottom of cake. Pipe tip 2 lattice work on side panels. Pipe tip 2 beads around ovals. Pipe tip 16 shells on top border and on vertical edges. Pipe tip 18 bottom shell border.
Position flowers and add tip 349 and 352 leaves to arch and on both cakes. Position ornament; attach doves.