I don't have access to 24 at the moment but I had a look at Door 23.
I don't use this door at all but I don't see any settings for a bottom frame.
I think the first image you show is a little misleading by Graphisoft.
There is a threshold but that will be at least the full width of the wall if extended both sides and it is not possible to make it the same as the frame width.
I don't see a way off adding a bottom frame, but as I say I don't use that library part.
Maybe someone who does may have a suggestion?
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
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