EU > Shanghai > Thailand > Hongkong> EU

I'm a EU Citizen planing to go to Thailand with a one day stopover in Shanghai. I will stay in Thailand for 2 weeks and than heading back to Europe with a 2 day stopover in Hongkong.

Actually it looks like that i'm allowed to get the 72h twov in China for my stopover in Shanghai - but i have some questions:

#1 What document do i need to show at the 72h twov desk that confirms my flight to Thailand? Just a booking confirmation print out with my name?

#2 I read that I also need to show entry permit of the country I will continue my travel. As a EU citizen I don't need a visa for a stay less than 30 days in Thailand. So i will not be able to show a visa at the Shanghai migration desk. Do you see a problem of not getting a 72h twov for China than?

#3 Does my 2 day stopover in Hongkong (on my way back home) has any influence on the 72h twov i would like to get in Shanghai?