Mid Ohio did good work on both my Busa's, they are a good shop. Plug your battery tender in and if the light turns green within about 5 min it's not a battery problem, but I know that thing has died on you, sometimes they just don't come all the way back:) That would be a simple fix and you would see problems under 4k RPM with battery issues. The FI light should not be coming on, you have stock exhaust and no PC on that thing, I am not saying ASK is full of it, but that is kind if strange to say something like that is just a bug. It could be a bad plug or a fuel filter problem, but I would think you would see problems across the board and not just at low RPM's.