One thing that really helps out a lot when creating new meshes for just about any game is vertex painting. What is vertex painting? Vertex painting is assigning color values to the different verticies of a mesh in order to make it look more realistic (ie darker around the edges or dirty). Look at the difference that vertex painting can make in the Elder Scrolls 3 construction set.
The thing that got me when trying to learn how to use this tool was a severe lack of information available on it. All I had to go on was a single web tutorial that was not designed for export into a game like TES3 and therefore did not render exportable results and a few tiny hints in the 3D Studio Max helpfile. It took a while but I eventually figured it out (mostly).
First things first for this tutorial I am assuming that you already have basic knowledge of how to use 3D Studio Max the TES Construction Set and you know how to export a mesh in NIF format. That being said we can start by opening Max and starting a fresh new scene.
We are going to keep this simple so in this tutorial we will be making and vertex painting a brick. We are also going to speed through the creation of the brick and get to the vertex painting because like I said before I am assuming you already know how to do this part of it.
Create a box object and give it several height width and length segments (6 on each should be sufficient for our purposes here) add to it a UVW map in the shape of a box, then create a bitmap texture and use one of the textures already on the TES CD I used Tx_stone_plain_01.tga. You should have an object in your perspective view that looks similar to this and renders similar to this
Now is the part where we get into vertex painting, one thing I want to stress here is that vertex painting is probably the LAST thing you want to do to your model before export. In my experimenting with this whenever I did something to the model after the vertex painting the vertex painting was almost completely invalidated and did not show properly in the Construction set. That being said next we add an edit mesh modifier to our mesh.
After adding the edit mesh modifier to the mesh we need to use the polygon sub object selection and select all the faces of the mesh that we wish to be able to paint on. In this case we are going to select all of them but that is not always the case. You will have models where you will want hard lines to show where one texture runs into another in those cases you only select the faces that you want to be able to be affected by the new colors.
Once we have the faces selected we add the Vertex Paint Modifier. In the Modifier List dropdown it is found under Mesh Editing.
Now in order to see what we are doing we will need to turn on the Vertex Colors by pressing the button labeled VertCol as pictured below. After doing this the mesh in the viewport should turn white with the paintable faces outlined in red.
Update
Now we are ready to start painting. Since we are only trying to make the edges of the mesh look dirty we will only be painting in black. Select the color black and the paint tool and start to dab the paint onto the edges of the mesh. You should see the color start to appear against the white, like pictured below.
Do this until all the areas you want to be affected by the vertex paint are covered, then turn off the Vertex Color (this is important because otherwise you will get a white model in the construction set). Now Render......Notice that when you render it looks exactly the same as before. No you did not do anything wrong at this point. There is a reason for this. Vertex Painting is only affected by light and in Max there is no light to affect it. This Mesh may look the same when rendered in Max but if you convert it to a NIF and import it to the Construction Set it will have all the vertex paint settings assigned to it.
Please note that I only figured most of this stuff out a few days prior to the time I am writing this tutorial. I may not yet have figured out everything there is to this. If you know an important step I have missed or if I have skipped over a handy feature of this tool please let me know so I can add it into this tutorial.