You can't type in Hindi using the STM software. The application has been developed by Tamara Systems and it allows you to change the clock in System Tray. In order to use the Hindi font, I suggest you download and install Google Input Tools. Navigate to the official web page, check the box next to Hindi, click the Download button, save the file to your computer and install it following the on-screen instructions. After that, from System Tray select HI instead of EN and you will be able to type Hindi on your computer.