You will find here a detail description on the leader board:

You can replace the number with the player name or if you want to use %player_name% just remove the "%" for example %bpm_player_name_game_value%

There is 3 types of board: win, loose, game.
There are two types of information: name, value.
You will need to choose a number going from 0 (the most) to the number of people that played the game.

A quick example will help you to understand:
%bpm_1_game_name%

Here we are getting the name of the second player that played most games.

%bpm_0_game_value%
Here we are getting the number of most played games.

%bpm_2_win_value%
Here we are getting the third number of most won games.

%bpm_3_loose_name%
Here we are getting the name of the forth player that lost the most games.