Hello Boris. I know that you already know about that Skylighting bug but i was doing some researches and found some more usefull information for you which can maybe help you fix this bug. I found that shadows suddenly changes only when you are rotating camera in each 180 degree angle exactly at same spot. But it doesnt cause shadows to appear brighter each 180 degree angle but I think that you just set wrong angle values for skylighting shadows only for 180 degree instead of 360 degree angle. So only 180 degree angle of scene is affected by skylighting shadows and another one doesnt what makes shadows appears suddenly darker/brighter when you are rotating camera. Also found those points of imaginary shadow split are one at North-West and another one at South-East so hope it helps too. Also included Image to clearly understand the problem.

http://bit.ly/WMAVaI

Another one color burn bug I found is caused by SunRays Effect. Also did some reasearches that may help you and found it can be caused by SunRays effect fighting with low AmbientLighting /AmbientLightingCurve values. Images Included showing the problem.

SunRays ON--http://bit.ly/UVipwm
SunRays OFF-http://bit.ly/WZeGya

Hi
Never saw myself such issue with sun rays. Ths should not happen in normal conditions, when colors are positive, i need preset which produce such bug (don't know what is set too high or too low) amd info what version is that.
Sky lighting bug is well known to me, why it appear, but simply don't have enough data to from renderer to fix it.

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