1 week in advance: Make gum paste trims for cake top.
Tint gum paste: 18 oz. yellow, 8 oz. orange, 4 oz. light violet, 2 oz. dark violet; reserve a small amount of white. Roll out 1/8 in. thick unless otherwise specified.
Using patterns, cut out yellow moon with tree in 1 piece. Set on cornstarch-dusted board. Cut orange tree; attach over yellow base using Gum Paste Adhesive. Use cutter to cut out pumpkin; set on cornstarch-dusted board. Roll out violet 1/16 in. thick; use pattern to cut out owl. Attach.
For trims, roll out gum paste 1/16 in. thick. Cut thin yellow and orange strips for pumpkin lines, white eyes for pumpkin and owl, light violet pumpkin nose, mouth and irises, dark violet owl wings, bow tie, nose and pupils for pumpkin. Attach all using Gum Paste Adhesive. Let dry 1 week.
When dry, attach Lollipop Sticks with melted candy. Carefully turn gum paste pieces over onto waxed paper-covered cake boards. Attach three 3 in. lengths where tree branches connect to moon and on upper trunk section. Attach 6 in. length to tree trunk and 5 in. length to pumpkin, leaving 3 in. exposed at bottom to insert into cake. Attach two 8 in. lengths to back of moon, leaving 5 in. exposed at bottom.