ok. cool.
Texture_D.dds is the diffuse it contain the color of the materials
Texture_S.dds is the specular file, it is represented by dark colors being less glossy then lighter colors. Metals need to have the brightness being white to make those area shiny. Best way to make this easily, it to duplicate the diffuse texture and bring the saturation down to almost no color, the using the level tool clamp the ranges a bit.
Texture_N.dds is The normal map, you can take a copy of the diffuse, desaturated it to grey scale and then save it as a normal map with the dds plug in.
For glass, opacity goes into the diffuse texture, as you have done in the files you posted.
There are other settings, but lets start with the basics first.
Put your x file, fpe, bmp and all the dds files into a folder. In the fpe file all you will need is the file names of the assets not the paths. think about if you need it static or dynamic and set it in the fpe file also.
Save the file and then set it in the editor and test it and see.
Most everything else is explained in that doc file I pointed to.
Hope this helps more.
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