I do use Milkshape the easyest thing to do is if it is a cylinder is Select the part you want to split the textures. and press CTRL+X it will CUT the part now press CTRL+V it will paste it now you can press MOve and move it into position now Only select once of the sections you cut and texture it.
Now un-select the part and select the other one.
Now Make a new texture and texture the Other Part.
Sorry if this is a bit off of what you want but that is what i thought you wanted
Thanks
Spuddy
Was Hi! but Hi! Was gettin a little iritating