Heat milk, brown sugar, ginger, cinnamon and cloves in a large saucepan on medium heat, about 5 min., stirring occasionally, until small bubbles form around the sides of saucepan.
Meanwhile, in heatproof bowl, whisk together egg yolks, sugar and cornstarch until smooth. Gradually whisk about 1/4 of the hot milk mixture into yolk mixture, then whisk contents of bowl into saucepan mixture. Cook on medium-low heat, stirring continuously 5 to 8 min., until custard is thickened. Remove from heat. Stir in molasses and vanilla. Strain the custard through a sieve into a bowl (discarding any lumps); cool completely. The custard will thicken as it cools.
Meanwhile, stir together thawed blueberries, honey and orange zest; set aside. In another bowl, roughly break up 4 cookies for garnish; set aside.
In 12-cup (3-L) trifle dish, layer in half each of the custard, remaining cookies, blueberry mixture and whipped topping. Repeat layers once more. Sprinkle with reserved broken cookies. Chill at least 1 hr. before serving.
Can be made a day ahead and chilled.
Substitute homemade custard with 3 cups (750 mL) tinned custard and stir in the spices and molasses.