Intriguingly, when I DR and load this family under the door category in Revit 2025, Revit blocks the loading, prompting the family is not a door. When I open it in the family editor and then load it into active model, it loads successfully and appears in the project browser under door category. However, when I DR, the door types don’t show in Properties. Then I created several instances with code, though no matter how I change the creation point, the instances always appear at the internal origin. And location property remains null the whole time.
Submitting a Revit ticket might help.