Salaam & Greeting

Q: Do we have to reply to someone who greets us by just saying 'salaams'?

Q:

1. Should I reply to the "assalamualaikum" written in an auto reply, because it's coming from the computer and is not verbally said? 

2. What is the ruling on typing "asak wr wb" and other similar short forms of salaam?

Q: If two people depart after meeting then saying salam is required or Allah Hafiz? 

Q: If a non-Muslim says Assalam u alAikum, how should we answer? 

Q: If a person is far away (so far away that he can not hear us) and we want to make salam to him. How should we do it? Should we say salam with the mouth and make a sign or just make a sign? How will this person reply to our salam? Will it be wajib to answer salam? Will he have to answer with the mouth only or by sign?

Q: To make Salam to others is sunnah. If a person does not ever make salam to others, is he a sinner? Can we blame him?

If a group of people come to another group and nobody in the group does Salam, will they be at fault?

Q: What to reply do I give if my non-Muslim friend says salaam to me?

Q: When making mu'aanaqah, should one put his head to the right or left? Some people go to the left and some go to the right sometimes causes a head bump.

Q: If I am very certain that if I give salam to someone, that person won't answer me back as it happens always. Should I give salam to that person  everyday when they enter the home or should I refrain from this as it is increasing their sins?

Q: What should the response be when a person messages with the greeting "Salaams" instead of the full AssalamuAlaikum?