Select the animal, and click on the Materials tab to go the the mat room.  Set the diffuse color to white.  Right-click on the blank area to the right and choose New Node--2D textures--Image map.  Drag from the plug icon in the upper left to the diffuse recepticle on the Poser surface box.  That should connect it.  Click on the word "None" and you can browse to the image you want to use.

Repeat for each material that uses the map.  Use the Materials drop down at the top to pick material zones.  When done click on the Pose tab to go back to the Pose room.

John