Hi, that is the basic idea (if its the scar across the nose).  You notice that it is white, that is the result of your white in the Blender node channel 2 and in the blender channel, it looks like the setting is around .5.  You may want to raise it a bit by plugging your texture node 2 also into the bump or displacement channel of your PoserSurface and adjust the number too.

If you are going for a fresh wound, place a reddish color in the blender node channel 2.

For your scar, if you can't get it to your satisfaction via drawing it in, you can go on line and look for scars, download the picture and cutout the scar and clean away the picture around it, convert it to black and white, and then position it over the nose (rotate it and adjust the size etc in PS).  Jan