You can convert EPUB to AZW3 with
calibre. But if you must use actual EPUB files on your Kindle, then try
KOReader.
You WILL still have to follow our sticky thread "Serial Jailbreaking your fw 5.6.x Kindle for Dummies", which requires work. But it should be doable if you have steady hands and are good at following directions.
In order to run non-Amazon-approved code on the Kindle, you MUST jailbreak.
Unfortunately, the only current way to jailbreak the KT2 and other fw5.6.x devices, is via the serial port.
All MobileRead hacks are open-source and are easily used via the serial port or however else you can get it on the device.
Duokan is a closed camp, which we have no involvement with. Their closed-source installer does not offer a serial port mode, and without their cooperation, there is nothing we can do.
Score zero for closed-source plagiarists.