You can use ScaleTexture on the texture you want to tile. Basically scale the texture the opposite amount you want to tile it (ScaleTexture tex, 0.25, 0.25) to tile it 4 times on the cube. An easier way to remember how much to tile it is to simply use:
ScaleTexture tex, 1.0/num_tiles, 1.0/num_tiles
ScaleTexture tex, 1.0/num_tiles, 1.0/num_tiles