A good tool for sorting out the AI traffic in your 'active area' is the
Traffic Toolbox SDK for FS2004. (Microsoft)
It installs a set of 'Tools' to the menu bar of your flight window.
In particular, it's 'Traffic Explorer' lists all AI in the 'active area' and their current state.

The info can help in modifying and/or testing flightplans.
Off topic: There are also several options you can apply to a selected AI aircraft.

One of the 'funner' :P options is 'Set Flight Plan' (to any parked ai). Assign any saved flight plan (*.pln) and the ai will fly it, including waypoints. This makes flying along more interesting that the normal ai 'direct route'.
Dave
At that time [1909] the chief engineer was almost always the chief test pilot as well. That had the fortunate result of eliminating poor engineering early in aviation.