Kenwood KPG-D3/KPG-D3E software is well protected and cannot be activated just by serial number (unlikely classic Kenwood KPG software).
Also, it's not hacked yet and is unlikely to ever be hacked.

THERE IS ONLY ONE WAY TO GET IT WORKING—TO BUY A LICENSE.

If you need KPT-300LMC licenses for the KPG-D3/KPG-D3E, as well as licenses for radios, consider purchasing them legally. 
We recommend you visit the fan club website nx5000.com, where you can find more information on the topic. In particular, a list of dealers who work with small orders, individuals, and radio amateurs: https://nx5000.com/dealers

DO NOT ASK US FOR FREE LICENSE, CRACK, PATCH, FIX, ETC. THEY ARE DOESN'T EXIST AT ALL! We will not be able to help you get KPG-D3/KPG-D3E for free.

And here in files we offer just official Kenwood files that require to be used with the KPT-300LMC license client and genuine Kenwood licenses.