Upgrade to the latest version!  It's easy with Twilight Render.  Just install over the top of your current version.

Make sure to read the release notes in the forum here!!

• Download the latest installer here.
• Save it to your Desktop, or somewhere you can find easily
• Just run the installer.  There is no need to uninstall your previous version
• Make sure not to delete your license file unless specially instructed to do so!  The same license will work on all versions of Twilight