The Night of Qadr according to most authentic Hadeeths is 19th or 21st or 23rd of the Month of Ramadan.

Most of our brothers and sisters who follow Sunni sects think that 27th is the most likely night of Qadr. This is because of the Sunni rulers who wanted to drive the Muslims away from the narrations and teachings of Ahlul Bayt (AS). 

In fact, there are many authentic Hadeeths in Sunni books stating that the Night of Al-Qadr is  19th or 21st or 23rd. (Nayl Al-Awtaar by Al-Shawkani).

Interesting question!

One has to assume that if the possessors of these books chose not to share them, then it is not necessary for us to know the contents. Mushaf Fatimah and al-Jafr, according to hadith, contain more than fiqh and shari'ah; for instance, according to hadith, they contain detailed future prophecies, and perhaps this information would not be beneficial for us. According to hadith, Mushaf Fatimah was narrated to her as a form of consolation due to her grief for her father, so from that angle, there may have been a personal purpose. 

Thank you for your question. The occurrence of Layaltul Qadr during the month of Ramadan is derived from the Qur'an itself. In surah al-Baqarah verse 185, God says:

"The month of Ramadan is that in which the Quran was revealed"

And the night in which the Qur'an was revealed was the Night of Decree as is stated in the first verse of surah al-Qadr:

"Surely We revealed it on the night of decree."

However, the Qur'an does not specify which night in the month of Ramadan lalat al-Qadr is and so the next step is to turn to the traditions on the subject.

Bismihi ta'ala 

It is Almighty God who appoints obligatory acts to His creation, and for us Muslims to comply to the commands and requirements given to us by Him. If the Almighty says that we pray in a particular way, and in another way when travelling, or to fast, and at times not fast, we must follow this.

Islam is a natural, understanding and forebearing, and the Shari'ah accommodates to our human needs. 

The condition of prayer is that one must be in the state of ritual purity, which means one cannot pray while in the state of Janabah, Haydh or Nifas. 

Bismihi ta'ala

The observation of the 'iddah period is not only to ascertain pregnancy, or not, but rather for many issues, and most importantly it is a divine ruling placed by Almighty Allah. 

As long as the marriage has been consummated, even though ejaculation did not occur, when the husband divorces his wife, she will still need to observe 'iddah. 

Bismihi ta'ala

This would all depend on what time of the day/night you are travelling, and when your are leaving your place of iqamah, which is the place of your residence or where you have intended to stay for ten days or more.

If you leave your place of iqamah after noon time, you must stay fasting. If you leave before noon, you must break your fast once you exceed the boundaries of the place of your iqamah. 

Bismihi ta'ala

It is said that the important night of Qadr is one of the odd nights of the last ten days  of the holy month of Ramadhan. The night of the 19th, 21nd, 23rd, 25th, 27th, 29th. The emphasised nights are the nights of the 19th, 21st and in particular the night of the 23rd.  

As for the night of the 27th, athough it has also been mentioned in Shi'ah narrations, it is the night usually emphasised on by our Sunni brethren.

And Allah knows best.