GPL is all about the availability of the source code and that’s it. GPLv2 says that “you have to distribute the source code and charge no more than your cost of physically performing source distribution” (which is for free in our case). This is exactly what we do.
GPL also says that “if you distribute copies of such a program, whether
gratis or for a fee, you must give the recipients all the rights that
you have. You must make sure that they, too, receive or can get the
source code. And you must show them these terms so they know their
rights.”. This is also exactly what we have done.
OSS is “gratis” if you use it with GPLed applications under GPLed operating gystems. It’s “for a fee” (you need to buy a commercial license from 4Front Technologies) if you use it in any other environment.
This is “all your rights”. If you redistribute OSS you must give the recipient “all the rights” you have (recursively).