1) JFK - KIX with a stopover in HKG. I don't think I can do it with a one way fare. Can I call and book a later connecting flight then the default flight? Under 24 hours. Or do I have to book HKG -KIX as a one way, using additional miles?
2) My return is Tokyo - JFK. I wasn't planning on CX...trying to book it as multi city, connecting in HKG tells me too many stopover or open jaw.
3) The rules aren't easy to understand. I think the booking system is correct. Is there a workaround?

Thanks.