madno, send me a site mail.
i have build the above props and i guess your issue is the AO setting of the lights in conjunction with the bump map of the walls.
i have some tips to resolve this.

The problem is, that poser cannot emulate real ambient occlusion and ambient light. therefore poser uses a "trick". Some of the bumps on the walls get interpreted as to be darkened. thats where the fractals come from.

Better would be, not to use AO on the lights, but to use AO on the material. I have some updates for you for better rendering results.

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