For the optimization of the texturing, Iv’e first blocked in the objects that is going to share the same UV map. This will give me information about how high-res the different maps should be. Then I used Cas to arrange the maps with the ” “. If that is going to be used you first has to combine the objects and then use that button. After that I seperated the objects again and started to duplicate the objects that I wanted to be in the same UV spot, for optimization.