I was hoping that you just had to create a room with points located at each small wall end like in the Room with curved roof 2.sh3d file joined to this message, but in fact Java 3D doesn't seem to be able to handle too many elevations in a single polygon.
Therefore the solution is to create smaller rooms with two small walls at max along it as in Room with curved roof 3.sh3d file.
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Room with curved roof 2.sh3d
(1993 bytes)
(Download count: 115262)
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Room with curved roof 3.sh3d
(2035 bytes)
(Download count: 115118)
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Emmanuel Puybaret, Sweet Home 3D creator
