Gross

The easiest way is to install protonup-qt, it’s a graphical frontend to manage proton versions.

Once it’s installed it should be in the Steam compatibility drop-down.

Have you tried Proton GE yet? In Chrono Trigger, everything works until you get to a cutscene and then it crashes on standard Proton, I think there’s a codec issue or something caused by the video. Could be something like that.