When you have decomplied the Traffic.bgl with the TTools AI traffic aid...you will get three source files....these are text files and one is for aircraft, one for airports and the other is for Flightplans...this is where you want your flightplans. Add them to the text file and save the changes...then you must select the three files in TTools and click Compile.

That is basically it, but if you are not familiar with TTools then you should go through the help file which comes with it.....commoner

....Not sure just how well I explained that but maybe somebody else will have a go....