Progress in the engineering design and assessment of the European DEMO first wall and divertor plasma facing components by Barrett, T, Ellwood, G, Pérez, G, Kovari, M, Fursdon, M, Domptail, F, Kirk, S, McIntosh, S, Roberts, S, Zheng, S, Boccaccini, L, You, J, Bachmann, C, Reiser, J, Rieth, M, Visca, E, Mazzone, G, Arbeiter, F, Domalapally, P