Can i use 72/144-hour visa-free transit?

Hello,

I've a question about the 72/144-hour free transit.

1: We fly from Daegu (South-Korea) to Shanghai and will be here for 4 days. After that we fly form Shanghai to Osaka (Japan). Can we use the 144-hour free transit?


2.1: We fly from Osaka (Japan) to Beijing, but we have a stopover in Shanghai to switch planes (1 hour 50).
After that one person is flying to Paris, can he use the 72 hour free transit in Beijing?

2.2: We fly from Osaka (Japan) to Beijing, but we have a stopover in Shanghai to switch planes (1 hour 50).
After that I'm flying to Taipei (Taiwan), but I have a stopover in Nanjing (China) to switch planes (3 hours) and than go to Taipei. Can I use the 72 hour free transit in Beijing?

3: I'm flying from Taipei to Beijing, but I've a stopover in Hefei to switch planes (3 hours). Can i use the 72 hour free transit in Beijing?
Marco