How to type in Tamil Typewriter or Tamilnet99 mode?
Click on 'Preferences->Change Keyboard layout' and choose 'Tamil Typewriter (Traditional)'.
Alternately, you can also right click on Azhagi's operating icon (in the right bottom of your
screen) and move to 'Typing mode' to choose 'Tamil Typewriter (Traditional)' or 'Tamilnet99'.