Welcome to YT
I will TRY to answer these for you but I am by far not a breeder, so hopefully one of them will be along to help.
1. I think twice is optimal (one day, skip and day so sperm can build back up and then again the next day).
2. Once the tie is broken, they should be separated. The female should always be held during the tie so she can't pull away and hurt the male.
3. Yes
4. I would count from the day of the first tie but I think there are a few different opinions on this.