I'm going to make some editor (and reader) for EU2 save game files. To do this I need to konw as much as I can about this files. Know every single keyword, to recognize and translate it correctly. There is much I don't know what it means, but let's start with 'nationalism' keyword withing 'province' tag in the beginning of the file. What does the date there mean? Thanks for your interest. 
Ederon
Ederon