Running the game on CLI does not work. Some games it works, others don't. There is a separate Proton 5 (in the game's directory) and the compatdata is within the Proton 5 directory. The script below is used.

#!/bin/sh GAME_TO_RUN="$PWD/ISEKAI QUEST.exe"

if [ ! -f "$GAME_TO_RUN" ] ; then echo "$GAME_TO_RUN does not exist!"; exit fi

echo "Now running\n $GAME_TO_RUN"

export STEAM_COMPAT_DATA_PATH="$PWD/proton-5/compatdata" ./proton-5/proton
run $GAME_TO_RUN
&> /dev/null

exit 0