As to follow up with some comments I received today, there is something I quite left out to mention using this "Hack". When changing from door category to generic (or other category) for the first time, if there is any existing element (e.g. Door frame, mullion, panel or glass) assigned to its sub-category, the assignment will be wiped out during the process once it is switched to generic model.
|Once this is set to Generic Models...|
A simple fix is to re-assign the specific elements back to the sub-category that they belong. That will do it!
My 2 cents here is to have this trick applied early to the door family setting before you start creating parameters or geometries in the family. I did this exact switch and use it as a door template when we re-built all our door families for the office.
Thanks to Sherry Pittman and Darrell Smith who are nice enough to email me this oversight. I would also like to thank Craig Uptmor here as he was the person who suggested the trick of switching family category.