Oh well - resolved the issue. I went ahead and removed all the sectors from the itinerary except the bare minimum to make it a DONE4 so reduced it to:
AMM-xDXB-HKG-SYD-MIA-MAD-DXB
and tried to ticket - it worked. So I bought it - figured I'll pay the $125 or whatever change fee + taxes to reticket it after the first segment is flown (AMM-xDXB-HKG) and redo the rest.
Hope this works :-( better the $125 change fee then the fare difference that ex-USA would be...
Nick