Update:
After an exhaustive (I mean that) uninstall of FSX completely from my system I began the clean install process (using Nicks guide) as always. After getting everything in order and defragging using O&O...I still have the ai_player.dll crash after FSX exits. This time however I'm using no AI program of any sort...none...nadda...zip...only default FSX AI which is currently set at 20% for both.
I however seem to have narrowed it's cause down to possibly relating to Vancouver+ V3. I use it as well as Victoria+ but if I remove Victoria+ (using scenery library) the crash still happens. Re-enabling it (Victoria) then disabling Vancouver+ V3 and the crash disappears. Both of those add-ons have a configuration app for removing the added AI objects/craft they offer but disabling them using their prospective configuration apps does not resolve the crash issue. What is odd (figuratively speaking) if I remove FSDT Vancouver and continue to use both the (Vancouver+ & Victoria+ add ons) the crash disappears. Removing Vancouver+ (while running FSDT Vancouver) from the scenery library resolves the crash issue as well. Appears like some compatibility issue between FSDT Vancouver & Vancouver+V3. Leaving Victoria+ has no ill effect with or without either of the other two.
This crash also only happens...1. After haven exitied FSX /// 2. Only when I fly the PNW region /// 3. Only when using FSDT Vancouver with Vancouver+V3. If I fly from an area outside that region I receive no crash after exiting FSX (when using both together).
What I have added since the clean FSX install:
Complete UTX series (all current versions)
GEX - Europe, North America, Atlantic-Pacific tropics, Africa-Middle East (all current vesions)
Current version of FSUIPC (current version)
REX Essentials Plus (current version)
FS Global 2010 (current version)
FSDT Vancouver, Los Angeles
Fly Tampa - Montreal, Dubai, St. Maarten, Hong Kong (old)
Wing Creation - Narita & Fukushima
Numerous 3rd party payware aircraft such as: Iris Simulations, Vertigo Studios, Aerosoft, Aircraft Factory, FS Developers, Virtavia, Nemeth Designs etc...
Just to add when selecting a location to fly from and choosing CYVR Vancouver (using FSDT) nothing shows up in the location box (it's empty). Is this correct? Choosing other locations from the Vancouver+V3 or Victroia+ add ons will fill the box up with a location.