Sorry I didn't focus enough on your questions.

I would recommend working directly with either of the two via e-mail.

The first step might be to get a full oneworld timetable (you can download it from CX's site) and work out the itinerary you wold like, even if the dates for most flights are left open. the current policy is that you have one stop leaving Australia and one stop returning. If you're in SYD you can stop, say in PER leaving and in AKL returning to SYD. When you land in a continent you have have 4 flight segments within that continent. The only exception is the US where you would be allowed 6 segments. You can have a maximum of 20 segments on the entire trip. You can buy a few additional segments within a country fairly cheap as long as you don't exceed the 20. (Other flights might be picked up on the cheap locally)

The reason to do this work before getting the ticket is that you pave to pay for changes made after the ticket is printed.

Once you have firmed the routing you want to take then I would contact either of the two office directly. Since you are going to be gone for a year the only seat availability concerns would be for the initial flights, which is easy to handle over the internet.

I doubt if you will get a discount from ENEMCO. They know that they have the cheapest fares in the world and sell a lot of them. They might, however, be able to get you a very good rate at a local hotel, things like that, but I'd be surprised to see discounts on the airfare.

NB. If you are going to stay away for more than 12 months then you need to buy your ticket after you leave Australia - the ticket is only good for 12 months. I would wait until you are into your trip and see if you want to make any changes to the routing, then get the ticket. Your departure city must be Cairo and your ticket will return you there, unless you get to Australia and throw away the rest of the ticket.