Straightening the saffs

Q: It comes in a Hadith that straighten the rows, the word "taraas" has been mentioned which means join like a brick wall with no gaps. So why do we not join the feet and only the shoulders. Also, what does it mean by close the gaps shaitaan will come in-between? Also, if the companions joint their feet an shoulders should we not follow them in the beggining of Salaah? And is it nessasary to join the shoulders? Please give me daleel as these are people's questions. Where I give dars.

Q: If three people are offering Salah in jamaat then how should they stand?

Q: How must the saffs of women be if the room is small? Can men muqtadis (more than one) read 1 foot behind the Imaam on right and ladies one saff behind?

Q: How should a woman perform salaah in jama'ah, if I perform behind my father (if we are on safar)? How do I make niyyah and what do I read in qiyaam, jalsah, qaumah etc. following the hanafi math'hab?

Q: In Salaah in Jamaat, when pulling a person back from the front saff to join him in the back saff so he doesn't read Salaah alone in the saff: 

1. Does he pull the person from the middle of the saff or from the side of the saff?
2. How will the front saff get completed again? 
3. If a third person then came and joined the second saff, can any one of them move into the front saff if that space is still open?

Q: Is it permissible for a person to stand alone in a saff in Jamaat salaah? If not, then what should the person do in this situation?