Personal licenses were only for FS V1s, all V2s can change OS' and have full functionality based on the tuning license(s) available (e.g. GM vs Cummins).

I would caution you against full flashing different ECM and TCMs OS', even within the compatibility guide. As GMPX said, there are under-the-hood changes that may brick the controller. I know the ECMs are more susceptible to it as the CPU2/DBW controller isn't flashed by EFILive and can brick. If you're trying every option, then maybe it's worthwhile but be prepared to replace the controller in certain circumstances.