Hi Filipehm,
The recruiters will speak in English and only in English during the whole process. I would actually recommend your friend, not to speak portuguese with the rest of the people when the recruiters are in front, i mean, if they are doing tests or group activities or whatever, they should speak in english even though they all speak portuguese, coz when i attended the open day, they mentioned it, and said to us that we should get used to it since during the 5 weeks of training we would only be permited to speak English.... I would also say to her, that she really but REALLY should wear a skirt suit, the recruiters themselves will tell your friend if she gets successful to the second day... My process lasted for 3 days.. so She should ask for at least three days off from work...
I am not possitive about the assessment/open day thing, but as i recall, the assessment day was only to be attended by people who had been invited, it is, those who got an email from the emirates saying they wanted to interview them.. and an open day is for everybody who wants to show up and hand their cv.. that is why they reffer to it as "open".
Hope my information is correct, and it is useful somehow....
My best wishes to ur friend... JANI