I tried the presenter and USB adapter on my Android phone. Couldn't find an application to test the forward / back buttons in, BUT the volume controls buttons did bring up a volume dialog, and changed the volume! So, the presenter is again tested okay, and the adapter tests okay too.
I suspect the KT3 is just different somehow. Since you wrote KindleLazy for yourself, and it works well on your PW3 (and even on jscris's KV by happenstance) you are quite within your rights to leave it at that.
But if you ever find what's different about the KT3 and put that in, well, that would be icing on the cake!
In short -- no pressure. If it ever works, I'll try it. If you quit with what you've got, that's fine too. Thanks for some cool software!
Oh -- when I press the button to start KindleLazy, it dumps me back to my book index. I imagine that's what it's supposed to do. If not, well then, that's another piece of data for you.