Sorry but, I can only repeat and confirm that, the only KNOWN causes for objects appearing ONLY when getting close or the reason why SOME objects are missing, is the "Compatibility" mode enabled ( by FSX or another add-on that runs together with it ), or the AAA.
If there was a problem with the software, you wouldn't see ANYTHING. No scenery at all, no buildings at all, just jetways. If you see parts of the scenery and some missing, and especially in a seemingly random pattern, it means everything is running correctly, and the problem is something else in your settings.
OR, another add-on which is interfering, maybe the Simconnect communication pipe is abused by this other add-on, so our software is running, but doesn't have a chance to communicate with FSX.
We had a couple of reports of these issues, they can only be found by disabling all your add-on modules in the DLL and EXE XML files ( except the Addon Manager and Couatl, of course ), then re-enabling them one by one, until you find the culprit.