Can confirm this behavior. This happened to me in LFBD while landing to rw 05 and chose to use rnav approach. - - The plane descended using vs mode to platform altitude but remained in alt* mode and never went to alt mode.
- MDA was set in the to/appr page
- The final x.xx was confirmed in to/appr page. VDEV appeared in that page and the it was below glide path according to it.
- NAV mode was the selected lateral mode.
- The plane was not past the FAF.
- Despite meeting these conditions, while pressing the profile button in fcu, nothing will happen, i.e not getting the blue P.Des and P.spd armed in FMA.
- if i don't do anything, the plane just flies level, I had to select altitude selector knob to mda and use vs to descend, i.e old school rnav approach.