Okay, I see the problem. You used the names from the root template items rather than their associated stat entries. When making item combos, you combine stats to produce an item with associated new stat.
So using the associated stats of the items you listed, your combo should work if you do this:
new ItemCombination "New_Stat_0"
data "RecipeCategory" "Potions"
data "Type 1" "Object"
data "Object 1" "CON_BodyPart_Dummy"
data "Transform 1" "Transform"
data "Type 2" "Object"
data "Object 2" "CON_Ingred_Dough_A"
data "Transform 2" "Consume"
new ItemCombinationResult "New_Stat_0_1"
data "Result 1" "POTION_Minor_Dexterity_Potion"
data "PreviewStatsID" "POTION_Minor_Dexterity_Potion"