Hoping this might help.
I think you know how to set the railing and baluster sizes.
Set the segment height and vertical offset as the balcony height.
Add rail 1 at the bottom (zero height).
Add rail to at balcony height (height doesn't matter if you are going to delete it but it is easier to add this rail - you will see why with the balustrade and panel).
Add balusters to the top section and a panel to the bottom.
I haven't found a way to add a panel behind balusters.
Now you can extend the baluster base to go to rail 1.
Then remove rail 2.
The panel will now automatically stretch to the top rail, but you can set it down by the height the top rail is above the balcony.
This is the result.
If you want rail 2 to remain just don't delete it and you don't have to adjust the balusters or panel heights.
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11