For example if you look at TK2, there are analog pins on the white plastic support, but behind it you will find a mixture of analog (S2 and S2.1) and digital ones (TK1s and US1 and US1.1). This is already confusing but the way the 5V and ground are laid out is even more confusing.
Here is what I understood so far.
As for the naming of the different groups of pins, I have found that the south digital pin is equivalent to TKD5.