Krell Home Theatre Standard 5.1 upgrade to V3.1

I have a question. I sent my HTS2 (5 channel) to Krell for repair so they also loaded the 3.1 software. I asked the tech support person what this meant and he begrudingly said something like 'it just makes things better.' Very vague. Can someone provide me with some details as to what the upgrade does? I did notice the rears were louder in Music Mode and the cutout between signals was better.

I am still learning things as I go so a reply would be greatly appreciated.

BTW, had a terrible time setting it back up because the original settings were gone after the upgrade. Thanks for any input!