Have you converted the BUM files for David (if they are called - I haven't installed yet but I know the beta had a PP Mat file, which suggests that there should be a P4 MAT file that will look for them). Go to Render>Materials, in the bottom left quadrant of the dialogue click Load and find the maps that need converting (look in Poser 4RuntimetexturesDAZCharactersDavid for names ending ...Bump.jpg), click Yes to convert, Cancel the Materials dialogue when done and try to apply the texture again.