Here is how I have added a texture map for the lips.

Open the last saved file, athlete_04.gmax. Select the skin mesh object and click on
the the Modify tab on the Command Panel. Select the Polygon sub-object level.
Scroll down to the Surface Properties heading and expand it if necessary. Click on
the Select By ID button to open the Select By Material ID dialog box. Type in the
number of the lips material, in this case 4. Then click on the OK button.Now we
have those polys selected.

Next click on Edit on the Menu Bar and slide down to Select Invert. Back on the
Command Panel click on the Hide button.

All we have showing now are the polygons that form the lips. Hit your Print Screen
key to take a screen shot.

Start your image editing software such as PSP or Photoshop and bring the screen
shot in to it. Crop it down to just the lip outline.

Convert it so you have just black lines on a white background. Make it a layer and
set the white to transparent.

I have opened an image with good detail of someones lips and cut and pasted the lips
into this image as a new layer. Bring the outline to the top so it over lays the lip color.
Scale and strech the lip color layer till it fits nicely to the lip outline. Once you have it
looking good, save it in a format that will retain the layers. Next flatten the image and
save it as a format that is usuable in gMax. I use 24 bit bmp most of the time so I save
mine to C:\gmax\Maps\ as lips.bmp. Also, I have taken a sampling of the skin tone color
value of the surrounding skin so I can change the skin material RGB values back in gMax.

Next I open the one I saved as layers and delete the outline layer and flatten again and
save it to C:\gmax\Maps\ as lips_texture.bmp.

Returning back to gMax, I open the Material Editor and the Material Navigator and
add the lips.bmp file to the material properties as a Diffuse Color map naming it
lips_texture.

Next with the polygons still selected, I add a UVW Mapping modifier from the
Modifier List in the Command Panel. Making sure the Gizmo is select and I am
working in the viewport that is perpendicular to the lips, in this case the back
viewport, I click on the Planar radio button, then View Align and Fits buttons.
It looks good enough to me, but you may want to fine tune the mapping with a
Unwrap UVW modifier. This is why I have the image with the poly outlines on it,
just in case. Once I have it like I want it, I Collapse the stack and unhide the rest
of the mesh.

Back in the Material Editor, change the map to the lips_texture.bmp... the one with
out the polygon outlines.

I have changed the Diffuse Color to the values I took in the image editing program.
Changed the Specular Color value as well as the Specular levels for both the lip and
skin materials. Don't forget to save your work! I saved it as athlete_05.gmax.

My character is looking better all the time, eh? Think I'll work on some eyebrows
next.