If it wasnt for the fact that you have already done a compression test I would swear that this sounds an aweful lot a bent valve(s). All the ish you've thrown @ it should have affected this in a positive way. I've experience this...not fun.
Keep fighting it man. Its crappy knowing there isnt anything I can do to help other than give support for a fellow KA owner.
__________________
If it has tires or boobs it's going to cost you money...