[Overhang warning - red surface confusing?]

Hello,

I exported from Rhino into Cura and some surfaces are highlighted in red. I understand that red normally indicates there is an overhang, however, in my model, some areas I would assume would be an overhang are not highlighted red, and others I would not assume to be overhangs, seems to be highlighted. See image. Is this a bug in Cura or am I thinking about it wrong?

Thanks,

-Margarida

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