I'm sure you will know the answer to this question
I have noticed for a while that certain games just wont display properly with the PSPUAE display option set to 16:9 setting or the 4:3 with auto zoom, I end up opting for the 4:3 setting, auto zoom off, screen lock on, then using a % zoom.
some games dont look correct in 16:9 zoom or 4:3 with full zoom, obviously out of perspetive or parts of the borders missing.
obvious examples are Dungeon master and Palaces barbarian
both games can be used with the 4:3 aspect with screen lock on and 34% zoom but this makes the screen size rather smaller (would be nice to have larger icons in dungeon master, to aid mouse navigation)
this begs the question - are there different screen sizes/screen resolutions for amiga games?
I just wondered because when dungeon master runs on the TTyman emulator it runs fullscreen PSP and the icons are much larger which makes mouse navigation/input less cumbersome.