So on my office machine, I have a single Roland A-Pro 800.
If you look at the first image below, you will see that there are three references, the first with no alias (because I don’t use) and then the second and third with aliases. My Roland sends control info (buttons, knobs, sliders) on port 3 and the keyboard itself is on Port 2
If I remove an existing association, by pressing the button with 3 dots and clicking on Remove MIDI device association…
then I get this - with the name of the alias in red indicating that the alias is not mapped to any controller
If I then click that 3 dots button again, I can select “Learn MIDI device”
and once I do that, the entry will change to indicate that it is “Learning…”
Simply press any key on your controller and the association between the name will be learned.
Then as long as all your MIDI In blocks are named MainKeyboard (or whatever name you want to use), you’re good to go. If they’re not named already, then you can right-click on the plugin block and set it
Once you are using aliases, then if the port name changes, simply open rig manager, learn the new controller (see above) and everything will then just work again.