You can find the hotkeys on the config menus if you want.
the lack of buttons in the new version looks like a bug.
You’re right, this was indeed a regression, introduced roughly a year ago it looks like. I’ve just fixed it, wasn’t actually too hard to track down. Can’t say when Lars is gonna make a patch that includes the fix though.
(if you’re wondering who I am: Lars has contracted me to do some work on DQ, in particular getting it to run on the Switch)