You may already be doing this but for those that don't know:-

• In UVMapper Pro select Texture/Auto Update.
• In your paint program select the whole texture and Edit/Copy. This sends the data to the clipboard where UVMapper will read it. (If its a very large texture then past your image to a new image, reduce its size to about 1000x1000 and copy that.)
• Back into UVMapper and select the chest area, then hit the Tab key to see the 3D view.
• In the 3D view go to View/Reset View to bring your selected area up close.
• Select View/Texture and View/Wire Frame.

You'll now clearly be able to see how your texture is being applied to the model. Adjust in your paint program, reselect and copy as required.

Hope this helps.