.bat script issues

[ThaUnknown_]

Code:

@ECHO OFF
TITLE Compress GIMP
CLS

REM This is to get the first argument after the batch file
SET FILE_IN=%1
CALL :DEQUOTE FILE_IN

REM This sets the path used in the gimp script
SET PATH=%FILE_IN%\*.png

REM This prints the path
ECHO Will run GIMP script in path '%PATH%'. Press Enter to continue or Ctrl+C to exit.

REM This waits for enter input
PAUSE

REM Change argument 0 to the GIMP exe
REM For me it's "D:\Programs\GIMP 2\bin\gimp-2.8.exe" 
REM If you want to run it inside the current cmd window,
REM  use gimp-console-2.8.exe, otherwise (aka new window pops up), use gimp-2.8.exe
"D:\Programs\GIMP 2\bin\gimp-2.8.exe" -i -b "(batch-auto-fix \"%PATH%\")"

REM Tell user it's done!
ECHO DONE.
GOTO:EOF

:DEQUOTE
FOR /F "delims=" %%A IN ('echo %%%1%%') DO SET %1=%%~A
GOTO:EOF

This is a script I asked my friend to make that changes the image mode to indexed and saves it as a compressed .png. He never could get it to work and he gave up so I figured this is the best place to ask for this kind of help. I hope his comments are enough, if not I could elaborate/explain if issues arise.