The new Cube Recipe needs to state that it can not be used with Crafted items, and it needs to state that only one of the newly created primal can be worn at a time.
Although this is stated in the patch notes, once it goes live, it needs to be stated in the recipe description so that there are not hundreds of bogus bug reports each season.
There are a few Recipes that do not work on crafted items in Kanai’s Cube. And it has always been that way. Hellfire Amulets and Hellfire Rings are Legendary items, but cannot be Reforged in the Cube. If you try, you’ll get the message that you cannot Reforge crafted items.
But, it does not say that on the Law of Kulle Recipe. If just says: Reforge Legendary.
Actually, some crafted items will work. I think the difference is: If you craft a Legendary item that can drop from other sources, then you can use the Cube on it. If it is a Legendary item that can only be crafted and does not drop in the game, then you cannot use the Cube on it.
Then, there’s that thing we (you, I, and others) always tell other players that post in the Live PC D3 Bug Report Forum: “Read the Season Blog”.
We have also added a Primal Item recipe to Kanai’s Cube, allowing you to upgrade any non-crafted legendary item to a Primal Item for 100 Primordial Ashes. Only one upgraded Primal Item may be worn at a time and upgraded Primal Items do not retain the properties of the Legendary Item that was used. New affixes are rolled for all upgraded Primal Items.