Some airports might not be resolved correctly in IF Pro since some recent changes in the scenery addons.
These changes are currently being included with IF Pro to meet the demands of addon scenery features.
We might try to build a flight and the flight might fail to complete, with perhaps a message to re-index.
That could be an airport with a feature not currently resolved by IFPro.
If we cannot build a flight we can try exchanging with other airports to check.
This what I mean when I might say you have to look to your simulator to find the problem. For example as mentioned try other airports. Uncheck airports in the Add-Ons menu options in P3D close and re-index IF to try the stock airport or whatever airport is below in hierarchy.
Similarly we might find the FSX versions of Ideal Flight can have similar issues with some airports. If I am informed of the problem I can investigate and fix usually very easily.
Thanks for understanding the problems that can emerge from systems that do not stand still for long.
Much thanks also for the support and compliments!