Unwrap is a wise choice, however it is possible in milkshape. Create your textures on your .bmp or whatever format. Then create groups in milkshape of the surfaces that you want to texture. You then select the Texture coordinate editor that is located in the "Window" menu of Milkshape and select each group and map it in the UV window that appears. It is kinda a pain, but it works. To tile map something, just enlarge the image of the section your working with larger than the texture. Hope this helps

It is easier with Unwrap.