Tank drive is very simple to program, and I believe that it is included in the default code, as an option. but here is what you would use as the code:
Code:
pwm01 = p1_y; //change 01 and 1 to appropriate joystick and pwm output
pwm02 = p2_y; //change 02 and 2 to appropriate joystick and pwm output
Thats basically it...
You put that in the function 'User_Driver' in place of whtever code you used, and its tank drive.