The only thing sure, it's that an ntdll error cannot be possibly caused by having installed the scenery. It's not so simple as just copying the UIAutomationCore.dll in the FSX root folder, it depends which version you are copying. Sometimes, it might be even better to have no UIAutomationCore.dll at all.
Don't even *think* to manually replace the ntdll downloaded from something else, this is a core OS file, if you are not totally sure which version your are using, chances are you are going to entirely mess up your whole windows by doing this.
Are you using the CURRENT version of the scenery installer ? Years ago, we used to place an UIAutomationCore.dll with our installers, trying to *prevent* crashes, but after getting many conflicting reports (some users fixed the crashes entirely with it, some *started* to get crashes with it) we don't install it anymore now. So, if you used an old Zurich installer that installed it, try to remove it, and use the latest Zurich installer.
If, instead, you already used the latest Zurich installer, the UIAutomationCore.dll didn't come from it, so you might try just removing it and see if it makes any difference.
However, ntdll crashes are not caused ONLY by UIAutomationCore.dll issues, there are dozen of other possible causes for it, like corrupted files, exhausted memory, etc. None of them is usually related to a scenery, problems with sceneries usually cause g3d.dll errors instead.
