What is the ruling on having brotherly ties between a strange man and a strange woman, and is the former considered a Mahram(unmarriageable) to the latter?

Such a relation between a strange man and a strange woman is forbidden in Islam because it involves forbidding what Allah has allowed by marriage, and allowing what Allah has forbidden such as looking and the like. Such a relation doesn`t render any act lawful between them, thus they are forbidden to look at each other, have a Khulwah(seclusion), and travel together.

Is it permissible for a person who has to make up for missed fasts to fast six days of Shawal(the month directly after Ramdhaan) before making up for the missed fasts ?

Yes, it is permissible for him/her to do so, but it is better that they make up for missed fasts first.

Is it permissible for a woman to swear a false oath by the Holy Quran to please her distrustful husband?

It is forbidden for a person to do so since this is considered a false oath(Yamaan Ghamoos) which dips(Yaghmos) its taker in Hellfire if he/she doesn`t seek repentance, and he/she has to expiate for that oath. You should avoid any doubtful acts so that your husband`s chest remains clear from the evil suggestions of the devil.

Is it permissible for the person who wants to travel from the United Arab Emirates to Jordan during the day in Ramadan to break his fast before leaving his country; knowing that he had embarked on journey half an hour after dawn?

Praise be to Allah the Lord of the Worlds.

The person who made the intention to embark on journey after dawn must observe fast for that day, because it became an obligation on him before engaging on journey. However, if he experienced unbearable hardship while on travel, then he is permitted to break his fast, but he must make up for the missed day. And Allah The Almighty Knows Best.