Once youre finished texturing, you need to complete the final few steps before you can export the model to create the CMP/inclusion into the mod.
To complete the mesh, you need to use of the symmetry modifier. Making sure your unwrap UVW modifier is now deselected (the yellow highlight should be grey), go to the modifiers list, find the symmetry modifier, and open it. Select the axis which will correctly complete the mesh, and mirror the mapped texture co-ordinates as well.
Having done that, right click on either modifier, and click the option collapse all to make the changes permanent, save copy as to ensure youre work is saved.