NZbutterfly Welcome to the QR forum.
I would recommend you look at the
http://www.flyertalk.com/forum/onewo...help-here.html thread for answers to most of your questions. there is also
http://www.flyertalk.com/forum/qatar...ect-miles.html with a couple of useful links. When you have a better idea of how you want to manage your miles then we can give you much more precise answers.
Any reply we on this forum gave you now would be rather generic and very complex. If you can decide how you want to handle the miles then we can give you much more precise answers.