Lesbentley is exactly right. The lines that begin with "usemtl" in the PP2 or CR2 are the places to change, along with the list of materials at the end of the file. When you build a prop from a mix of imported objects (or Poser primitives), Poser takes the materials from each and piles them up at the bottom of the PP2, then puts a "usemtl" statement in the main paragraph for each of the pieces. The Preview and Preview:1 and so on will usually be duplicated many times so you can't match them by name. One trick I find useful: Generate one super-simple PP2 file for each actually used material, consisting of just a Box with one of your materials applied. You can then pull out the entire Material paragraph from these unambiguous little files, and copy it over into the lower section of your real file. For instance, apply your Walnut colors and textures to a box; save it as WalnutSample.PP2; then copy the paragraph under "material Preview" in this file into the real file as "material Walnut". Or, if you can see which of the Previews matches this identically, you can just rename that Preview to Walnut. Once you have all the actual materials with meaningful names in the main file, you can get rid of the Preview stuff, and be sure every "usemtl" in the upper part refers to one of the properly named materials in the lower part.

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