@Keet
You have partially right.

So no problem with the door because it stays the same height

Indeed but at different X and Y.
If you look closely to my first two picture you could see I've arranged the doors at same Y and the corresponding X.
After I open the door (Thanks God wasn't a Window [;)]) the bounding box has been modified and of course the X and Y BUT,
somewhere in the code Emmanuel compute the necessarily corrections so the door frame appear to stay in their position and only the door has been moved.
I need this correction to be made also for Z.
I've tried to find the responsible part of code but maybe I've don't try hard enough.