I'm sorry I emailed you first. Normally I use the forums because I like to get input from more then one person. Your forum is the only one I ever had to wait for being approved
You need to be approved, because we take the burden of manually approving everyone (it would be FAR easier for us if it was automatic), to protect YOU against spammers, that register to the forum only to spam and harvest users emails.
And you wrote that I was meddling manually with files!
You wrote that you were meddling manually with files, here:
I just installed FSX on another computer (just to get the Airplanes folder) and replaced all my Airplanes in the Airplanes folder
If the intention was to test on a fresh FSX install, there was no point in manually replace all your Airplanes folder after installing because, if just one of them had a problem, you would end up duplicate the same issue without understanding what was.
Instead, if your install was really fresh, without installing anything else (other than the obvious FSX service packs), you would surely realize that Hawaii 2 didn't crash, because it doesn't.
Hawaiian Airports Volume 2 must be looking for an AI airplane that don't exist.
That's not how FSX works. The airport doesn't "look" for any specific AI, the file that decides which AI goes where, it's the traffic.bgl, which contains all the AI schedules.
The AFCAD that comes with Hawaii2, controles only *where* each AI will park at the airport. And, in some cases, you might see more AI with the Hawaii2 AFCAD, because with the default one there might not be enough parking spaces, so AI might disappear just after landing. That's the only difference the AFCAD makes.
Another thing is when I'm able to get into one of the Airports in Hawaiian Airports Volume 2, it gives me the fatal error exiting the airport

.
Maybe it's just the same issue, if you could give a look at the Windows Event Viewer, it might be possible to have an hint were the crash happened.
You just seem to want to blame everything else but your airports. I'm sure more people maybe with similar hardware and FSX settings will be running into this problem because there's nothing wrong with the AI but most likely the way Hawaiian Airports Volume 2 handles them.
Fact there's nobody else having this specific problem, clearly proven otherwise. Since, according to your report, the airport crashes 3 times out of 5, we should have been flooded by similar reports by now, but instead you are the only one so, it's clearly not a problem of the scenery.