FSX shared skies + complex planes

Hi,I recently read a post saying that the "shared skies" feature found in FSX will only work with default planes (or, for other planes, will only support functions found in the defaults). Is this true? Is it possible for a developer to design a complex airplane (like, for instance, a re-designed PMDG 747) that will feature full "shared skies" functionality (all custom switches will be synchronized between "shared skies" players etc...)?Any info on that please? This feature is one of my favourites and I'd hate to see it limited to the simple default functions...regardsSpiros HazapisAthens, Greece