The virtual FS9 directory is needed because of the auto installer.
Just make a folder call it FS9 and place a copy of the FS9.exe Inside it, and that's where the auto installer will put everything.
When that's done, move the planes & scenery over to FSX, and then convert the flight plans to FSX version using AIFPC (free).
It's not hard to do, the reason they don't do it themselves, is because it's not meant for FSX. If they did, they would have to field all kinds of support questions for problems that are caused by trying to put the square peg into the round hole.
Posky is the same way. ;)
WOAI and PAI have come up with an installer that will do all of this automatically, so I'm sure the guys at MAIW are cooking something up.
FS9 isn't going to last forever (as much as I would like it too.
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