The three files you need are:
-player_information.csv (created by 'Export Data')
-rookies.csv (created by 'Export Data')
-draft_personal.csv (created by 'Export Personal Scouting Data' or something like that)
Draft Analyzer will let you scroll through / resort / reorder / evaluate a draft class quickly, and it's useful because the native FOF application believes the best way to do this is to manually click on each player to see his bars. Without it, I don't know how anyone would manage to evaluate a class.
During multiplayer drafts, it's also very useful for marking players as drafted and removing them from your pool of players left to evaluated. That way you can see what's still on the board and what's not.
If you're having trouble locating the files (the game should tell you where they are), do a Windows search for
Code:
leaguedata type:folder
As I recall, with Draft Analyzer you have to point it at the folder containing all three files and it'll work from there.