Indeed, this is annoying, to say the least. Why not follow midi specification if offering “Program Change” capabilities? And why not providing any information about a sequence of midi messages that would allow for PC? It is not only Reaper, GigPerformer (the software side), NO, also my hardware - an Novation SL MKIII, resp. the hardware synths I am using - which can not successfully be used for routing PC to Halion if not using it standalone, making it practically unusable for a live context. For me this smells like a “use Cubase or die” or “use Halion only” policy. How could I not test this before purchasing a license. I must be stupid to expect something working which was always working and is common and reasonably expectable behaviour in the context.