After prayers, folding a corner of the prayer with a concern that the Satan might start praying on the mat has no basis.
 Fatawa Rahimiyyah vol 2, pg 302
The Friday sermon is not merely a speech or a talk but is in fact an essential and integral part of the Friday prayer and such must be delivered as prescribed by the Prophet, that is, in the Arabic language. A similar example is that of Adhan (call to prayer) which must be called out in Arabic language. We know that the companions of the Messenger of Allah, peace and blessings of Allah be upon them all did not change the language of the Friday sermon to the native language of the lands they conquered even though there was obvious need for the people to understand the sermon being delivered to facilitate their learning of the new religion. In other words, Arabic is the official language of Islam so far as the religious rites are concerned even if it may present a significant problem in people comprehending it.
Though, certain other schools of Islamic Jurisprudence allow it to be delivered in languages other than Arabic, it is more precautious and safe to do so in Arabic as has been the practice of more than 1300 years of Islamic history.
Dr Saleem narrates the article wrote by Mufti Muhammad Taqi Usmani db in Urdu.
Part 1: (duration 13:16 min)
Part 2: (duration 10:09 min)
Part 3: (duration 2:50 min)
If a mature woman prays next to a man without any partition, it will nullify the prayer of man if the Imam leading the congregation intended to lead women as well. If however, the Imam didn’t intend for women congregation, men’s prayer will be valid but woman’s prayer will be invalid.
When in such a situation, one can ensure the validity of prayer by doing one of the followings:
If he is praying behind the woman, then an arm-breadth wide plank should be erected in between or he is above the head of the woman. Failing to do any of these will nullify his prayers.
When praying fard salaah at home it is better to pray in congregation even if there are only women available.
The woman should stand behind the leading man even when there is a single woman praying along with him. This is different when two men are praying together as they stand side by side with the imam’s heels slightly ahead of his follower.
 Ahsan ul Fatawa vol 3, pg 365; Fatawa Mahmoodiyyah vol 16, pg 228