Minor updates may add additional functionality to FSI Viewer or fix some known issues and are available for free. A minor update increases the 2nd or 3rd digit in the version number, e.g. version 4.0.6 to version 4.1.5.
Major Updates increase the first number of the version number, e.g. version 4.1.5 to version 5.0.0 and contain new features and functionality that has not been implemented before.
You can check your current FSI Viewer version by enabling the debug window.