Found (old) issue in render... the "VlakRen" (render face) has an Object
pointer which can point to a duplicated one (dupliframes/dupliverts option),
which is freed before actual render starts... this nicely crashes in Windows.
I now store the original Object pointer, which can lead to texture
orientation errors in some situations (like normal-bump stuff).
Real solution is recode of duplicator system!
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