Dorico did let me change the expression map to the Iconica contra in play mode, it was on the list (exactly as on the left side of your screenshot). But then there were only random saxophone-like sounds coming from the contrabassoon, even when it had no notes in the score at all….
I opened the Hallion software for the first time now, but I have no idea what to do there nor how to get to the list in your screenshot. I’m sorry, I’m really not good at this. I don’t understand why the program doesn’t automatically choose an instrument that can actually play the notes I write. I mean, when I choose a playback template, there are several of the different sound libraries written after eachother (“HSO, HALion Sonic Sel., Olympus, GASE 2”).
I found out in the end I had to click on the “e”, but they really could not have hidden this more. So I managed to recreate your suggestion from your screenshot, and that works. Thank you! Now I know what to do if other instruments make problems!