In Poser 4, I find I have to select the item I'm texturing before going into the materials dialogue. If I select it from within materials, and use the 'apply to all' feature, sometimes the textures get screwed up - applied to the wrong things, or just not showing properly. Save / exit / re-open seems to fix it, but I just avoid doing that any more. If the 'apply to all' box isn't changed, then it doesn't matter.