'Spare' here means plain and simple, without ornament.

None of the examples you give need the -ing form. 'Not watch TV' is not the right imperative form. It should be 'don't watch TV'. The second example can use the bare infinitive - 'You should help your brother, not just sit there' - because 'should' goes with both 'help your brother' and 'not just sit there'. 'Tell her to not live apart like this' isn't the usual form either - 'tell her not to live apart like this' would be more usual. Or it may be addressed to the friend, not the woman: 'tell her to move back in; don't live apart like this'. So the correct versions are: - If you're not going, then wash the dishes, don't watch TV. - You should help your brother, not just sit there. - If you still love her tell her to move back in with you, and not to live apart like this. OR - If you still love her tell her to move back in with you. Don't live apart like this.

Your second suggestion is closer. The idea is that the wax model was a representation of the artist, and the photograph was a representation of the wax model - so the photograph was a representation of a representation. That's why he calls it 'a double move'. (The text you quote is very obscure; if you can understand it you're doing a lot better than most native speakers would.)

Yes, they are both correct. You might omit the exclamation mark, though, and the second 'are' in the question.

You can if you know him well, and he's an equal - a fellow-student, for instance. I wouldn't call him Jimbo if he's your teacher or priest or boss. He might consider it disrespectful.

Yes, I think you've understood it well.

It means that not much was said about it.

Yes, that's correct. You could also have said, 'How long did you work . . '