mate
that curtain walling can only be used as an
object rather than a window element. it means you need to place an emtpy hole in your wall first. it's a bit of an inconsistency.
also. that particular curtain walling will give you curved glass as well. whilst this is possible, in reality it's so expensive that is almost never done. i tried once to re-script it for straight/faceted glass, but my GDL knowledge wasn't (and still isn't!) up to it.
HTH
~/archiben
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