FE,

I'm not familiar with My Traffic 2, but I suggest the following:

If you haven't already, download the latest version of AFCAD and create a new facility file from scratch to accompany the airport you designed in FS Scenery Creator.

The procedure for doing this is well-explained in the AFCAD manual.  Once you have done this, you should create a new entry in the Traffic.bgl file, including the ICAO symbol, coordinates and elevation for your facility.  Not being familiar, I'm assuming that your traffic editing program will allow you to do this.

Once that is done, you should be able to create AI flight plans for your airport and (with AFCAD) manipulate the direction of traffic in and around the airport.

Good luck,

Erik