"Adesso a casa non abbiamo la luce."
"Now we do not have light at home" should also be accepted as a valid translation of this sentence.
i think it should accept "•Now at home WE have no light." and not accept "•Now at home have no light."
"Right now we do not have light at home." should be accepted as well, as the 'right' clarifies that it's referring to the present instant and not a change from a previous situation as 'now' alone suggests.