So, it appears that P3D v2.1 didn't include any fixes needed by the FSDT Hawaiian airports. As a comparison, I went over to FSDT KLAX's runways (believed not to contain any FS8 content), and was able to stay at about 50-60 FPS.
Unfortunately, while LM initially promised to have a look at this, they said very late in the beta cycle they might not have the time instead.
This, of course, doesn't affect just the FSDT Hawaii airports, but probably HUNDREDS of 3rd party sceneries for FSX, many of them which might not be updatable (old sceneries, freeware, etc.). And I still believe this bug might be just a symptom of something more serious, like a memory leakage, so it should be addressed in any case.
As we said, the plan was that, in the event that LM failed to fix this bug, we would provided an alternative solution, which is something we'll surely do, but it takes a bit of time, since we need to create two different set of files for FSX and P3D, and update the installers to handle the difference, and update even the Live Update procedures as well, something that wouldn't be needed if the problem was fixed on the sim side, but we'll do it anyway...
