This must be the same path than the %VPROJECT%.
Directory where the mdl and vmt and vtf files will be exported on your hard drive.
%GAME_PROJECT% is an environment Variable that must be set before you run Maya with MESA.
You can edit that path into the projects/GAME/game_project.bat file, by replacing the path of the Environment variable that is named ” %GAME_PROJECT% ”
MESA 1.1 :
do not exists and only use the %VPROJECT% variable
MESA 2.0 / 2.01 :
you must to restart maya to apply the environment variables modifications.