I've used the 60616 door plenty times and it's fine.
You don't want to "import" the part, you want to use the standard Edit/Add/Part function to add it to the model.
If you keep unofficial parts in a dedicated folder for unofficial parts then you'll need to paste the full path into the custom part path box. If instead you keep copies of custom parts in the same folder as the current model then you can simply browse for the part.
You don't want to "import" the part, you want to use the standard Edit/Add/Part function to add it to the model.
If you keep unofficial parts in a dedicated folder for unofficial parts then you'll need to paste the full path into the custom part path box. If instead you keep copies of custom parts in the same folder as the current model then you can simply browse for the part.