Quote: "I have a mesh, a sword with a handle, a blade, and a handle ring. When I export it as a .x file its one mesh"
Quote: "then do I have to export each part of the sword, assign the textures and shaders, then group them together in dark basic pro (if that is possible)?"
If these parts are separate objects in Blender you can apply separate textures to them with Blender's UV editor, then make separate bumpmaps for each of those textures outside Blender.
The Blender parts/objects will be limbs in an exported .x file and in DBP you can then get the limb texture name for each part and use that texture name to apply the correct bumpmap/shader.
One thing i though, you can't multitexture limbs (not sure about separate shaders). I use this method to make objects from limbs and that method maybe of no use for you as the sword is a combined entity. Maybe have the sword handle, hilt and blade as separate objects and glue them together would work?
Regards