As far as Sonar playing on after the song is supposed to end. I have had that happen but I just hit the stop and the song stops.
Looking at it that way, to call it a bug to me is bit premature. If after you take a long hard look at the total events in that project you mat solve the issue.
The notion of having to select a time range isn't a bad idea but even so editing the resulting wave file will do the same thing.
The only problem is waiting for the end to occur.
Most if not all causes for this behavior is due to some event further out on the time line. In the past we would advise that using the Event List to see if something is placed way out is present has generally proved effective.
The reason I just said I hit the stop is because it weas an unimportant issue for me with that song and I didn't want at that time to investigate it further.
Other songs stop when they should so it has to be something in that project.
What really bothers me about your story is they came to you for your creativity. They wanted to "pick your brain" for content in their project. If you delivered that content they have no gripe what so ever and the next time they try to humiliate you you need to explain that you provided exactly what they asked for. If that is not good enough for them than in future tell them to seek out some one else they can kick around. I have to wonder what was going with them and just how much payment you received from them and if it wasn't a way to not pay what your contribution was actually worth.
Creativity is the most expensive of any project and is often not given the value it should get simply because the ones with the money don't want to pay for it.
They will abuse anyone in order to keep their costs low. DO NOT LET IT EFFECT YOU.
They are using you, don't let that happen ever again.