Hi,
there's no way to check what color value the plugin would use for a specific aircraft, but it shouldn't be too difficult to get your plugin to behave similarly in most cases.
As far as I remember, the two most visible changes are a custom color for tracks in the notified state (Color_Concerned), and displaying that color also for tracks in the coordinated state if they haven't departed yet (GetFPState() not FLIGHT_PLAN_STATE_SIMULATED). There may be other differences as well, I don't really remember the default behavior very accurately.