Prayer

If you pray it, Allah will reward you. if you don’t pray it, Allah will not hold you accountable for not praying it.

It is not recommended as it would distract you but it is permissible.

It should be done in any prayers that have two tashahuds.

No, this is recommended but as long as you say rabbi ighfir li, this is sufficient.

You must try to figure the direction of the qiblah by a compass. You should also pray standing up. If this is not possible, you may pray sitting down. If you can’t pray sitting down to the direction of the qiblah, it is ok to pray due to necessity.

It is not part of the masjid and people pray in it as they pray outside in the open area due to the rows are connected.

It is correct. one can pray voluntary prayers until the Imam comes out. As for the interval between the two athans, this is wrong. It should be longer than that so that people would prepare for the prayer.

You must not walk in the space between his feet and forehead when he prostrates.

No, but it is highly recommended if not mandatory to say it if you are in a city that doesn’t announce the athan and it is recommended to say the iqama for every prayer.

I know that Ibn Masoud prayed in the masjid alone for this reason. However, the majority of scholars say that it is permissible to pray 2nd congregation in the masjid and this is the most authentic opinion