To use your own avatar inside the game, you need to create a bmp image file to the following requirements :
Height : 76
Weight : 97
Bit Depth : 24bit
Place this file into the following folder :
C:\Program Files\UBISOFT\Chessmaster Grandmaster Edition\Data\Avatars.
Give the file a name such as "Sam.bmp".
Then edit the Avatar.ini file which looks like the following :
Please add your own avatar to the list, so in this case add "3=Sam" on the end of the file. Or use the name of the file which you created earlier.
Then restart the game, and you will be able to select this as your avatar.