Shanghai to Kunming to Chiang Mai

Has anyone else on this forum traveled thru KM either or both ways from Shanghai to Chiang Mai? I am wondering if anyone has experienced any problems in KM with regards to not having a Chinese Visa. I am slightly concerned because I have a 13 hour layover there, but I understand my time in China starts when we land in Shanghai. (US Passport).
Also, what are the prices of the hourly lounges and are they worth it? Traveling with my wife and a 9 year old. Do they accept credit card or is it cash only?

Thank you