I got 13 also. Some were blatantly obvious, others were quite tricky I found because it's hard to establish a genuine smile when you've only got the one smile to judge it on. For me I found that the eyes tend to give it away most of the time, but as stated before it is tricky to spot 100% of the time.
That Chinese-looking lady has a dang good fake smile. I thought it was real. And that bloke with a goatee near the end has a real smile that looks fake.
I won't say anymore because I realise that people can look at these comments and cheat.
I do myself pretty hard on asian-type smiles. My wife is from the Philippines, and for me, they all look the same and when they smile, hmmm, I never know