Thanks for explaining. I was curious to why this memory corruption only trips SMP, nothing else. However, following what you said in the posts above I inspected my custom scenery folder and found that I have two LEBL custom sceneries (the Aerosoft one and the one I downloaded). I disabled the Aerosoft one using the custom scenery ini file, and tried again the exact same route, and encountered no CTD on the way. Safe landing this time!
Thanks again for the explanation.