It's still crashing at the Mastercard secure payment bit.

But on the positive side, at least you have then made the booking, been able to review all flight choices leading up to your booking, and have got your booking into their system. And almost certainly they have got your credit card debit through to Mastercard and it has occurred.

Now you just need to confirm things and get your booking reference. You call Emirates (I use the main Dubai call centre which runs 24/7, and has nice English speaking operators) with the flight number, time, and my name, and they will go into the system and retrieve the booking and give you the booking reference and send you a confirming e-mail.

A bit slow and clunky, but when you are on the road, in backward_holeville_south, it works for me.
Their number is +971 600 555555.