Mudbox can import UV
            texture coordinates onto a model in the 3D View. Supported
            file formats include: .obj, .mud, and .fbx.
         
         Importing UV texture
            coordinates onto an existing model is useful when:
         
         
            - The model you are sculpting in Mudbox
               has no UV texture coordinates. That is, its possible to sculpt a
               model without UVs. UVs are required when you want to perform any
               texture extraction or paint work.
            
- The model being sculpted currently has
               existing UV texture coordinates that require an update for any number
               of reasons. Since Mudbox has no feature to edit UVs, this must be
               done in another 3D application. As a result, sculpting and texturing
               work can occur concurrently in separate applications and the UVs
               updated on the model later in the production pipeline.
               NoteUpdating the UVs
                     on a model within Mudbox that has pre-existing textures could result
                     in the textures not appearing as expected, depending on the changes
                     that occurred between the old and new UV coordinate layout. It is
                     recommended that paint/texture work be performed only when the UVs
                     are final.
                   
            - UVs can be imported to only one model
               at a time. Do either of the following:
               
                  - If one model is in the 3D
                        View, proceed to step 2. 
                  
- If two or more models appear in the 3D
                        View, select the model you want to have the UVs applied
                     by selecting it in the Object List or
                     using the Object select tool in the Select/Move tools
                     tray.
                  
 NoteUVs can only be imported
                     onto the base subdivision level of a model (Level 0). Use the Page
                     Down key to return the model to the base subdivision level. For
                     more information, see  Increase a model's resolution.
                   
 
- Select File > Import UV.
               The file browser appears.
                
- Select the model file whose UVs you want
               to import and click Open. 
               An Import
                     Options window appears.
                
- Set the Import Options as
               follows:
               
                  - If the model whose UVs are being imported
                     is topologically identical to the model in the 3D
                        View (that is, has not been edited in any way that would
                     affect the number of vertices or vertex IDs), select the Match
                        by: Vertex ID option. This is the default setting.
                  
- If the model being imported is identical
                     to the one in the 3D View, but has been edited
                     in some way that has resulted in a modification to the vertex IDs
                     or vertex order, select Match by: Position.
                     This option attempts to match the UVs based on the world space positions
                     of the vertices on the model.