MkeJ, IDL bounces: test with diffuse. Set it to 0.5 and bounces to 40 and 3 (after trying some other values). Seems to me the lower the diffuse value is, the lower the brighten effect of more bounces. I learned something. Export to LS, I will try the obj export (will take some time to get used to LW - unfortunately not much time because of job).

pgmeri01,
thanks for the offer, but BB is right, no AO in that scene, no bump, no nothing. Just Poser primitive boxes tranlated into walls and bed tables. Two point light and IDL.

prixat,
your render shows, what I thougt to get out of Poser 8, something without all the artifacts.

jfbeute,
you are right, my thread title is not accurate. I should have written "Should I quit Firefly?"

jdcooke,
valuable links, thanks.

Generally,
realistic, truthy, art: not searching for that at the moment, just trying to render some walls, a ceiling, a floor and two bed table boxes without artifacts.