'Macao' vs 'Macau' 

I am afraid it is the other way round - 'Macao' is English and 'Macau' is Portuguese. E.g. look at the cover of a Macao SAR passport - the full name of the Macao SAR is written as 'Região Administrativa Especial de Macau' in Portuguese and 'Macao Special Administrative Region' in English. 'Macao' is the English name and 'Macau' is the Portuguese name - this is recognised by Macao and its sovereign state.

However, both are acceptable in English. It is just like using 'Munich' or 'München'. I am not trying to say that one of us is right and the other is wrong, I just want to draw your attention to the origin of 'Macao' and 'Macau'.