Although it's a far cry now from MRU as in the thread topic, I thought I'd add my own tale to Gardyloo's experience ex-NRT. I set up the itinerary with the RTW desk, and just got off the phone with AA in Tokyo to have it issued. The lady spoke very good English, so no problems there. She initially claimed that CX would have to issue the ticket, as my first flight (NRT-HKG) is with them. We argued a bit, she put me on hold for a while, and then said it'd be no problem to issue the ticket.

It should be an e-ticket as I canceled enough segments from my original itinerary to keep the count below 16, including open-jaws. We did the whole credit-card thing, and then she proceeded to read back the entire trip to me, flight by flight. I didn't really have the heart to stop her. Anyway, here's hoping all goes well with the issuing of the e-ticket as time is starting to run short.

All in all a very pleasant experience with the AA RTW desk as well as with AA Tokyo. ^