Hi Mala - when you purchase MoI along with your license key you also receive a download link to the installer for the full version. You need to use that installer in order to get the full version installed which will then ask you for your license key, the full version is a totally separate installer from the trial version.

If you can e-mail me at moi@moi3d.com and give me your license key or your name and e-mail address that you placed the order with I can then e-mail you back a new download link for getting the installer.

Thanks,
- Michael