Ok the problem is that you started from a very old script, so lot of what you copied is deprecated style...
You can check in the tutorial what current scripts should look like.
The use of $REPERTOIRE is deprecated, use $POL_USER_ROOT instead
No script will be accepted with rm not using absolute paths anymore. Anyway, this is totally useless, just remove it
Obsolete statement, just use POL_SetupWindow_Init
Also it should be followed by POL_Debug_Init to enable the embedded debugger support.
#set the prefix
Obsoleted by POL_Wine_SelectPrefix and POL_Wine_PrefixCreate
#set the Program Files variable
No longer necessary, $PROGRAMFILES is automatically set
POL_SetupWindow_message_image "Please note that this game requires a subscription.\nThis script will only install EverQuest II,\n it will not give you a paid subscription.\n\nDo not install shortcuts with the installer.\nThose shortcuts will break EverQuest II\nand correct ones will be setup later." "Note about subscriptions/shortcuts" "$PLAYONLINUX/themes/tango/warning.png"
POL_SetupWindow_message_image is no longer supported, use POL_SetupWindow_message instead.
And all user oriented messages must support localization mechanism
POL_SetupWindow_download "Please wait while EverQuest is downloading" "Downloading" "$DOWNLOAD_SITE"
use POL_Download instead
You should use POL_Wine wrapper instead of directly calling wine, so its output is correctly logged
POL_SetupWindow_message "Press forward only when installation is fully complete." "Confirmation of Installation"
Such user interaction shouldn't be necessary anymore, worse case if the installation is non-blocking use POL_Wine_WaitExit here
POL_SetupWindow_auto_shortcut "$PREFIX" "everquest.exe" "$TITLE" "$TITLE.png" ""
Use POL_Shortcut instead
Set_WineVersion_Assign "$WORKING_WINE" "$TITLE"
Per-shortcut Wine version is no longer supported, just remove that statement
Not necessary anymore
POL_SetupWindow_Message "EverQuest Veil Of Alraris has successfully installed.\nClick forward to close the window." "Installation Successful"
The use of "Success" messages at the end of scripts is deprecated, because it will be displayed even in case of non-fatal error, and then followed by a PlayOnLinux screen telling some error happened. Just remove it.