The source code is included, but you do not get resell rights so you can't resell the script with your changes at a later time.

It should be possible to do the modifications you want, but please remember that Xavier Media can't help you in that work. You have to do it on your own.

I don't know anyone doing the changes you're mentioning, but I now that some people have changed it from a pop-under exchange to an exit exchange without any problems.

/Andreas