Hi Guzzi.
Sadly, this is not a response, it also only an opinion.
I don't think that any software on this platform is on position to offer a great software support because of the size of this market. Also, software supports is an struggle everywhere, on MS, IBM, Oracle and even Apple. But you have the reason when you say that it is un-realistic for a software that you paid 4 years and 3 versions ago that offers great support. It is something similar to what is happening to Android today, you pay $1.00 for an app and you have eternal updates? That's sound strange, it is because the model will fail eventually and the developer will need to find a way to squeeze more money to keep developing the software.
Maybe:
1) If the developer does not have any more interest on fixing the software, maybe we can kindly request him to open source the software to have the possibility for someone else to fix it. It is very hard to fix close source software since it only belongs to one person.
2) Maybe you can share the problem with the community to see if there are other people that have the same issue and what comments they have about it.
This is why I like open source software, it may have bugs, it may not be perfect, but at least you have a chance (even if it is remote) that someone can fix it.
Regards