Have you had any luck yet? I'm looking for a Joseph Lux, from somewhere near Cologne, Germany, too. We thought he might have been born around 1850, as one of his sons was born in 1877. I'm not sure of his wife's name, or parents names either. I guess we're both chasing opposite ends of the tree!
Joseph had 2 brothers, we think, named Otto and Charles. Joseph had 2 sons - Anton and Charles, and 4 daughters - Anne, Emma, Frieda and SOPHIA (which is why I thought they might be related).