Just checked and am pretty sure it will be the sun settings.
Go to View > 3D View Options > 3D Projection Settings
At bottom of that window there should be a button More Sun...
Set the colour of sunlight and ambient light to a white (or very light yellow / blue colour). This should fix it.
Erwin Edel, Project Lead, Leloup Architecten
www.leloup.nlArchiCAD 9-26NED FULL
Windows 10 Pro
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