Hello jlaiho and welcome to the forum.
I am sorry to hear about the problems you are running into.
Didn't MIDI Program Change handling change in VST3?
As this is primarily a user to user forum, someone-else may chime in. Meanwhile, the best thing to do is raise a
Support Ticket, here for some one to one help (US (East Coast) Business hours, generally). Response time is usually within 2 working days.