A) a large mirror (closet door, but not finished)

B) sliding glass doors to the outside world......not that i'll ever go there

C) wall, yet its having a "mirror" effect and showing the sliding glass doors? material is fine

D) the lovely glass is making shadows! yet lighting is set fine

C and D seem to be only seen in reflections, if i turn the camera for direct view, works fine
all updates are installed 

Increase photon count to 20,000 - 50,000 so there's more diffused light bouncing off the mirror to the camera.  Set Interpolation to 100% to remove most of the ashes without taking too much of a render hit.  Check that indirect lighting can also travel through transparent objects.

since my post, i already tried at 20k, 40k, 50k photons
interpolation already at 100%, effects stay if i turn off, but then black spots on walls :)

trying to get my scene to be lit completely from indirect lighting, so ofcourse light through trans is on
if anything, my settings are too high, 2 hours to render this is not fun =P

appearently the reflection value from the glass doors reflects light onto the wall
the glass was only 2% value in reflection though -_- far from being a mirror
the effect isn't there in a direct view, only looking at it thought the mirror

tested some other scenes, seems to only happen when the view is reflected multiple times

Have you tried setting the glass so that it doesn't cast shadows?

glass is part of a solid mesh, which has to cast shadows
otherwise it defeats the purpose of the  indirect lighting :)