Hi Eddie ,yes they can be.

I just tried, I assigned settings to a few of the buttons and saved different setting to different registrations. They changed as I pressed them.
My first 4 registrations which I hadn’t saved with Assignable buttons setting, the button functions remained the same.

There’s about 16 items you can save as part of registration, you tick what you want.

Actually on the bottom of the main screen, there’s the assignable icon, if one needs to just refresh their memory as to what is saved, via the buttons, the screen pops up and you can see it and do any changes.