No, that is not using the 'corner window' tool.
It is an old window back from around version 6.5 that we still use (amended of course).
It just uses the WALLHOLE (actually now it uses the WALLNICHE) command.
But maybe that is it - the siding maker doesn't use the WALLHOLE as it obviously is not cutting trough the entire wall thickness.
But without access to the code, only the developer could help.
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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