OK, so I'm creating a new thread as a follow-up on the one linked below, since it seems I'm not trying to get JACK to work, but rather PipeWire "pretending" to be JACK (pipewire-jack, I think?).
Also, I've discovered sticking to Flatpak has its advantages, if possible - sources say it's hard to get Yabridge to work with it (and that it's generally hell on DAWs) but I can't be the first to have a go 
I found out that installing Reaper with the included .sh script yields a Yabridge-enabled install, but it completely refuses to acknowledge the Zorin-included pipewire-jack or any MIDI inputs. I can "force-start" JACK with QJackCtl & then Reaper can connect to it, but it breaks everything else; the system can't even see my audio interface anymore. And MIDI still doesn't work.
In other words, FP-Reaper does everything except Yabridge, non-FP-Reaper does nothing except Yabridge. Seems like the former should be the shortest route to success 
Referring to my previous thread I did try getting FP-Reaper to work using Flatseal (thanks @Ponce-De-Leon ), but all I know to do is turn on everything that isn't on - I don't know how to use the other options (screenshot below, in Danish but I think the option headers are the same).
I suspect that it might be something about adding certain file paths - also, I saw somewhere that permissions for Wine, which for Zorin I assume means Bottles, also have to be modified in Flatseal. But which & where?
Does any of this make any sense to anyone? I know I'm being longwinded & posting a lot but... I want to become a convert 
(Note: If you're wondering why I'm not asking this on the Reaper Linux forum, it's because they won't let me in - I created an account a week ago & still don't have posting privileges. Also, because you folx seem really cool & helpful 
)
