First thing is possible. 

But you do have just two travel days in your country of residence. So it would be just possible to do several trips to your home country by buying tickets for (I assume) Italy. 

Yes of course. Many people do this, travelling by car, bus or even plane when it’s more convenient.

In your home country, you can only t.travel on two days. They don’t have to be the first and last days of your trip though.

1. Yes, perfectly possible. It’s a great way to do hikes e.g. from, station A to station B.
2. No. you have the right to travel in your home country with the pass on two days. (The so called inbound/outbound travel days).
   If you have used all the inbound/outboud travel days. want to go way and back more times to your home country, just buy a ticket to/from the nearest border station. Once you’re abroad, you can use your pass again, Best keep the inbound/outbound travel days for the most expensive tickets ;)