This thread has been derailed, because DLH7LA converted into a generic rant against FSDT, adding other issues caused by conflicting AFCAD that don't have anything to do with this thread, which is about KLAX.
That floating object at KLAX, which I still cannot reproduce, it's not a problem of a conflicting scenery, since that object IS part of our scenery but, obviously, we surely haven't placed it in the air ( and of course it works with FSX and P3D 1, 2, 3 and 4 up to 4.5. According to your reports, it's only happening with V5, so it's likely a problem caused either by a setting or just an DX12-specific issue but again, unless you could give me some precise reproductions steps, it's impossible for us to even START working on a fix or a workaround, assuming a fix is even possible, and instead the bug will just go away with an update of the sim, just as the supposed bug at KORD V2 ( we also had a floating building there ), which was fixed with an hotfix.