Bump was going to be the first tip to reduce 'weirdness'.
The reflection is due to refraction and the angle of your camera (and thus the light). To clarify, picture from wikipedia where a polarizing filter is used to change the angle of the light
https://en.wikipedia.org/wiki/Brewster%27s_angle#/media/File:Poloriser-demo.jpg
A dirty trick is to enable 'reflect only floor/sky in the options > general options of cinerender (when you go into detailed settings).
Other option is to just add the picture of the sky to reflection channel.
Lots (and I do mean LOTS) of in depth info is here:
http://helpcenter.graphisoft.com/guides/archicad-20/archicad-20-reference-guide/user_interface_refer...
Erwin Edel, Project Lead, Leloup Architecten
www.leloup.nlArchiCAD 9-29NED FULL
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