What is the ruling of Islamic Law on colleagues alternating overtime shifts and receiving wages for absent days?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
An employee is religiously obligated to abide by the instructions and regulations pertaining to overtime hours. Furthermore, it is mandatory to adhere to honesty and avoid deceit, circumvention, and falsehood. Allah Almighty says (what means): "O you who have believed, be conscious of Allah and be with those who are truthful."
(At-Tawbah/119).
Therefore, whoever is assigned to work overtime must remain present at the designated workplace, even if no active tasks are required of them during that time.
Likewise, the official authorized to approve overtime work must comply with all established conditions and regulatory guidelines. It is impermissible for them to grant overtime hours in violation of system regulations. Should any compensation be disbursed in contravention of these official rules, it is unlawful to accept or consume such wages. And Allah Almighty knows best.
What is the ruling of Islamic Law on supplicating with other than the transmitted (Ma'thur) supplications in prayer?
All praise is due to Allah, and peace and blessings be upon our master, the Messenger of Allah.
It is permissible to supplicate (make du'a) during the prayer for anything from the affairs of religion or worldly life, and the prayer is not invalidated by doing so.
Shaykh al-Islam, the Imam an-Nawawi, may Allah have mercy on him, says: "Our madhhab [i.e., the Shafi'i madhhab] holds that it is permissible for a person to supplicate during it [the prayer] with anything that is permissible to supplicate with outside the prayer, from the affairs of religion or worldly life. He may say: 'O Allah, grant me wholesome sustenance, offspring, a house, and a beautiful young wife' — describing her; or: 'O Allah, free so-and-so from prison,' or 'destroy so-and-so,' and other such things — and none of this invalidates his prayer according to us. And this is also the view of Malik, ath-Thawri, Abu Thawr, and Ishaq." [Al-Majmu', Vol.3/P.454]. And Allah, the Exalted, knows best.
How many Rak`ahs (unit of prayer) are offered in Witr prayer?
All perfect praise be to Allah, The Lord of The Worlds Witr (an odd number prayer performed between Isha`a and Fajr) is offered with a minimum of one Rak`ah, and a maximum of eleven, but offering three Rak`ahs is the minimum of its complete form. And Allah Knows Best.
Is it permissible to combine and shorten prayers at home before traveling?
It is impermissible to combine and shorten prayers at home before traveling because a person is called a traveler once he/she departs the borders of his/her country, and offering prayer that way was originally intended to exempt a traveler. And Allah Knows Best.