Disregard them, assaultcube does not even use gourad shading. Models are simply illuminated globally, depending on the light intensity where they are placed - wich means all lightning has to be painted on - very old fashioned.
To save vertexes, weld the whole model i.E. put it all into one smoothing group only.
To save vertexes, weld the whole model i.E. put it all into one smoothing group only.