works for me too. fps = ~25
like ace1000 wrote must create (create as user. when i create as root it doesnt work) directory /home/user/.ppsspp

in settings we must tick only:
buffered rendering
hardware transform
(on screen touch controls)

game working:
GTA Vice City (3fps)
GTA Liberty City Stories (3fps)
Tekken 6 (some kind of loop so cant start menu)
Dragon Ball Evolution (game menu starts but cant start playing)
Boble Puzzle (menu starts, game doesnt start)
Tales of Eternia (10fps)

overlocking: 600 - 1150mhz