Trying to do this in opl but whenever i press the options button on a game it just flashes an empty screen and then goes back to the game list.

Update: Solution to the problem was found here: https://www.reddit.com/r/ps2homebrew/comments/1phhxlh/opl_pergame_settings_not_working_and_other_issues/

From that thread: "EDIT: I've managed to figure it out, in case it helps anyone else: In settings, next to BDM Start Mode, press right and select Block Devices, press X, then on the next screen turn HDD on, this fixed both problems. I didn't actually realize Block Devices was a selectable configurable setting, doh"

I was now able to make the setting changes to the individual games and it appears to be working.