Wish Bear,

I guess I'm a little confused by your question, but I'll try my best.............

You have been able to use add-on aircraft in the AI flight plans.  This tells me that you are using some sort of traffic editing program.  In regard to your changes not being saved, any time you use your traffic editing program to make changes to the Traffic.bgl file, whether it's a new flight plan, airport, or aircraft, you must always run the Compiler afterwards for the changes to take effect in fs2002.

You want to manipulate AI traffic so that it parks in specific locations.  This is what AFCAD is designed to do.  So if you haven't already, I suggest downloading the latest version of AFCAD.

In regard to the helicopters, I don't know which aircraft you are working with, but it may not be designed for AI traffic use.  I have avoided using helicopters in AI traffic altogether because they behave like fixed-wing aircraft rather than a helicopter.

Hope this helps!

Erik