[quote=94989]Solved by myself:
I have recompiled the libretro-fba project from the repository:
https://github.com/libretro/libretro-fba (2015-04-15)
And Neogeo savestates work flawlessly on Raspberry Pi 2.
[/quote]
The default in RetroPie is fba-libretro
https://github.com/libretro/fba-libretro
as opposed to libretro-fba
A bit confusing, but there you go.
Discussion on it here: