Well, talk to me on AIM and I'll go over the flag stuff with you.
What I did, when I first set up the GE version, was take the entire list of players in an Excel document, and mark off their country in another column (along with colour and times page in seperate columns), then just sorted the Country column alphabetically, and added them to the specific updater needed.
This will be much harder for PD, since there are so many people, but you could perhaps start with the top 100? Or do the whole list, and figure out as many as you can, then post it here or in the chat and others can fill in the blanks.