Dear Fr. Simon,
First of all, it is a pleasure to be able to get in touch with my fathers, brothers, and sisters in the Faith through this forum. I am John Fam, and I am Coptic Orthodox. I'm Egyptian, from Alexandria, Egypt. I've been looking at this topic about kissing priests' hands, and I've been looking at the incident you were describing, Father, when you were greeting a Nun in an Egyptian Convent the way Coptic priests greet each other. The thing is, what you described is commonly a method of greeting between two priests or bishops, but commonly when a nun greets a priest, she would kiss his hand just like any common person would. She isn't usually greeted the way priests greet each other (by turning the hands sideways), because she does not have the rank of priesthood. Perhaps that's another reason why she was surprised, besides the fact that she didn't get the blessing of kissing a priest's hand.
I went to a private British school as a child, with British teachers and some British classmates, so I kind of have a general understanding of British culture, and of Egyptian culture of course. So I think the hand-kissing issue is , as well as being a difference between Coptic and British traditions, is also related to cultural differences. Anyway, they do not affect our Faith.