MVO Background Fill overrides Foreground ... why?

[jakubc7]

I have 2 Model View Options for elevations.

MVO #1 - Presentation
Override Fill Background NOT CHECKED

MVO #2 - Documentation
Override Fill Background SET TO OVERRIDE TO TRANSPARENT

My window glass surface material is set to a FOREGROUND FILL (SOLID) PEN #174 ...

However in my MVO #2 elevation - what should appear as a light blue glass fill (and yes I tried changing it to a darker colour) it shows as transparent background. If I change my glass vectorial hatching to any other NON SOLID hatch it shows correctly.

Why is ArchiCAD overriding a foreground fill? Is this a bug or is there some logic behind it?

Any feedback would be much appreciated.