I thought of doing one when I find the time. It's pretty easy once you've figured it out, but getting there is painful. I would have loved a simple guide that at least explains what needs to be done in NifScope. There's a russian tutorial somewhere, but it didn't work for me. If there is a proper tutorial somewhere, I could not find it.
Basically, it's just a few steps for a basic mesh:
(0.: You should have your bump map (and gloss map if you want one) ready)
1.: Right-click on the NiTexturíngProperty in the Block list -> Texture -> Add Bump map, then choose your bump map texture
2.: In the NiTexturingProperty's Block details window, open "Bump map texture" and set the filter type to "FILTER_TRILERP"
3.: If you don't want a separate gloss map, skip this step: Add another map the same way as in step 1 and choose your gloss map. The gloss map can't be added directly, so I always select "add glow map".
In the TexturingProperty, double-click on "Has Glow map" to deactivate it again. Then double-click on "Has gloss map" and open the list that turns active now. Insert the number of your gloss map as "Source"
4.: Repeat 1-3 for all the textures you want to have bump maps on. (Note that this guide will enable the environment effect for all parts of the model, so there will still be a shiny gloss effect if you don't assign bump/gloss maps. There should be ways to exclude parts of the mesh, but I didn't need that so far so I haven't tried it yet
)
5.: Right-click on the NiNode in the Block list -> Block -> Insert -> NiT... -> NiTextureEffect. It should appear with a 1 in front of it
6.: Repeat, just add a NiS... -> NiSourceTexture this time. This one should be number 2 now
7.: Click on the flower icon in the NiSourceTexture item that appears -> Choose your environment map
8.: In the NiTextureEffect's details, add your env-map by entering 2 in the "Source Texture" field.
9.: Go to the NiNode's details, increase the "Num Children" by 1 and add the NiTextureEffect (by entering 1 in an unused Children slot)
10.: Do the same with "Num Effects" and "Effects"
11.: Save
I hope I didn't forget anything