I'll take a stab. In the first auction double would clearly be penalty, given you've already made one penalty double. 4NT should then be take out, showing a 2 or 3 suiter and partner should bid the lower of his suits. With the two suiter, if partner bids one of your short suits, you correct to your long suit to convey your hand type. Double is penalty, like I said, and partner's double would also be penalty. So his failure to double suggests that double with your hand is very risky. Whether or not you should bid 4NT, I'm not sure. For it to be right requires a lot of distribution from partner, and there is no reason to expect he doesnt have some ♠ length. I'd probably just pass and try to go plus. On the second one, 4NT shows 2 places to play.