Hi,
I would imagine you will have the least amount of trouble unmolding a jello mold that has chocolate in it if you temper the chocolate before you paint or pour it into your mold.
I have made a Jello 1-2-3 "like" product. Here's the recipe and some photos:
3/4 cup boiling water
1 package Jello, any flavor (4 serving size)
1/2 cup cold water
Ice cubes
1/2 cup thawed Cool Whip (or other frozen dessert topping)
Directions:
Pour boiling water into blender. Add Jello. Cover and blend at low speed until Jello is completely dissolved, about 30 seconds. Combine cold water and ice cubes to make 1 1/4 cups. Add to Jello and stir until ice is partially melted. Then add whipped topping; blend at high speed for 30 seconds. Pour into dessert glasses. Chill about 30 minutes. Dessert layers as it chills. Garnish as desired.
Combining Jello and water.

Blending in whipped topping.

Finished product in the bowl.
I hope this helps,
Ms. Ingie
Ms. Ingie
Life is too short, why skip dessert?