Quote - Hmm. It's really hard for me to see what is in those images that are used in the wall shader. It looks like a photo or render of some machinery, although I can't exactly correlate the render in the first post with what I see in the wall material.

I know this has nothing to do with your problem, per se, but that material makes no sense to me whatsoever. Is that supposed to be a transparent wall and we see machinery behind it? Or is it supposed to be reflecting machinery in the room? Or is it supposed to be a painting of machinery on the wall?

-Beats me, but the wall is not transparent.

In any case, none of those would justify using a photo of the machinery as a bump map on the wall, which is what you've got there. 

If I were you, I'd remove all that crap and make the wall a flat color with no specular, unless you mean for the wall to be made of something shiny. This is an apartment, right?

-I will try that solution!

Meanwhile, if I understand you correctly, what we see on the wall is some sky and what looks like a stone. Is that right? And you say that is the image attached to an IBL? (You said IBL AO, but that makes no sense. AO is ambient occlusion and we don't connect an image to AO.)

So you're seeing the image in an image based light projected on your wall? Could it be you forgot to set the light type to IBL? Because if you have it set to some other type, such as infinite or spot, then an attached image is like a gel or slide in front of the light. In such cases, the light would behave like a slide projector, and whatever it shines on will show the image, just like using a projector.

-Well, I haven´t forgotten anything, the lightset I have used here (in this example) was    included in my Poser 7 copy.  As I mentioned before, same issue occurs whatever IBL lightset I use!

If I haven't guessed right, come back. If you do, could you show me the light material settings and properties + parameters of the light.

If there's any doubt about what lights are doing what and you have more than one, I'd do a render with one light at a time.

In future, don't ever bother showing me the "Simple" material version - that doesn't show what is really going on. The nodes show me the true setup.

-Hear you!