The following describes known texture extraction limitations in Mudbox 2009.
Extracting texture maps when a vertex on the model has a valence greater than 10 (That is, more than 10 edges converge at a single vertex on the model) may produce unpredictable results in that location in the resulting texture map.
Workaround: Construct polygonal models in such a way as to avoid vertices with a valence greater than 10 before importing as an .obj to Mudbox. For further information, see Troubleshoot texture extraction.
Smooth Source Models option produces faceted results
The Smooth Source Models option in the Maps > Extract Texture Maps window may not work as expected and produce faceted results in the extracted normal map.
Workaround: Additional subdivision of the model prior to texture extraction may improve the resulting normal map (provided you have available memory). Facets in the normal map may still be apparent in some situations.
