Hi, sorry about that. In SFO for Xmas visit with the kids. I will work on the bug as soon as I get back. Hang tight! 

BTW I appreciate the detailed description. Makes it much easier for me to track down the problem.

Two additional things I need to know:

(1) What is the exact coding of your USBUIRT.BAT
(2) Eactly what you have in the Location field

USBIRT.BAT file contents....

:: This batch file is called by DVD Profilers-LoadDVD's USBIRT.bat file. It is
:: setup to run ISO, MP4 and DVD formats.  DVDs and MP4s will run without any
:: special setup.  ISO files must first be mounted.  Slysoft's VirtualCloneDrive
:: is used to mount the ISO image.  The virtual drive is setup to automatically
:: play DVD files with WinDVD.
::
::
@echo off
set TEST=No
set isoprgm="C:\Program Files (x86)\Elaborate Bytes\VirtualCloneDrive\vcdmount.exe"
set isoprgmparams= /I=I
set fullscreen=" /fullscreen "

:: Kill all previous instances of this batch file
:KILLPREVIOUS
FOR /F "TOKENS=1,2,*" %%a in ('TASKLIST /V /FI "WINDOWTITLE eq Administrator:  LaunchDVD"') do SET MyPID=%%b
if %MyPID%==No GOTO CONTINUE1
TASKKILL /pid %MyPID%
GOTO KILLPREVIOUS

:continue1
Title LaunchDVD

rem %1 Disc Description Side A
rem %2 DVD UPS code
rem %3 disc #
rem %4 slot #
rem %5 DVD Title
rem %6 filepath in the notes section
rem %7 Location Field
rem %8 mediatype = "DVD", "HD" or "BluRay"
rem %9 and thereafter - remainder of Location field

:: %6 starts and ends with "".  Must remove all quotes
set filepath=%6
rem echo %filepath%
set filepath=%filepath:~1,-1%
set filepath=%filepath:~1,-1%
rem echo %filepath%
rem pause

if %TEST%==YES (
echo Disc Description Side A = %1
echo DVD UPS code = %2
echo disc # = %3
echo slot # = %4
echo DVD Title = %5
echo filepath in the notes section = %filepath%
echo Location Field = %7
echo remainder of Location field = %8
echo .
echo .
)

for %%s in (0,1,2,3,4,5,6) DO if (%%s)==(%4) GOTO SLOT
for %%d in (NAS,0,1,2,3,4,5,6) DO if (%%d)==(%7) GOTO LOCATION

ECHO Bad drive number in the location field. The number must be between 1 and 6.
ECHO The Location is currently set to ( %7 ).
pause
GOTO END

:SLOT
IF %4==0 SET DRIVE=V
IF %4==1 SET DRIVE=V
IF %4==2 SET DRIVE=V
IF %4==3 SET DRIVE=V
IF %4==4 SET DRIVE=V
IF %4==5 SET DRIVE=V
IF %4==6 SET DRIVE=V

:LOCATION
IF "%7"=="NAS" SET DRIVE=V
IF %7==0 SET DRIVE=V
IF %7==1 SET DRIVE=V
IF %7==2 SET DRIVE=V
IF %7==3 SET DRIVE=V
IF %7==4 SET DRIVE=V
IF %7==5 SET DRIVE=V
IF %7==6 SET DRIVE=V

if %TEST%==YES (
ECHO DVDPATH = "%DRIVE%:\%filepath%"
ECHO %isoprgm%%isoprgmparams%"%DRIVE%:\%filepath%"
)

if NOT exist %DRIVE%:\NUL GOTO NODRIVE

::if %TEST%==YES GOTO END

::test for iso file
echo.%6 | findstr /C:".iso" 1>nul
if errorlevel 1 (
  start %DRIVE%:\%filepath%
  GOTO END
) else (
  %isoprgm% /u
  TIMEOUT /T 1
  %isoprgm%%isoprgmparams%"%DRIVE%:\%filepath%"
)

:: Loop and wait for ISO to stop playing then unmount the iso image
:ISOLOOP
  TIMEOUT /T 300
  tasklist | find "WinDVD.exe"
  echo errorlevel = %errorlevel%
  if %ERRORLEVEL%==0 GOTO ISOLOOP
  %isoprgm% /u
  GOTO END

:NODRIVE
echo Drive %DRIVE% does NOT exist. Check the USBIRT.bat file.
pause

:END
if %TEST%==YES PAUSE


Location Field Contents...
The only thing I have in the location field is "NAS" (no quotes).  Nothing in the slot field.

I have been using LoadDVD (not Pro even though I purchased it) for a long time.  This is the way I have setup the location and slot fields from the beginning.  If I remember correctly, this happened once before and you corrected it.  I hope I will not have to go change 800 profiles to make this work as before.  BTW, I have "Call USBIRT.bat before play" selected in the options of the LoadDVD Plugin.  I use the Location and Slot numbers to tell me what hard drive the digital file resides on.  The slot tells me which portable hard drive the file is on.  I may be using this plugin different than it was intended but I sure like it.  It would be really nice if the location field was passed to the usbirt.bat file regardless of what is in the location field.  I will check out your playing ISO users guide on your website.

Thanks again for the great plugin.

Just about got it. I did find one inconsistency that I want to fix, and looking at your script, I don't think it will impact you.

I found that the filepath was wrapped in single pair of double-quotes when USBIRT is called normally, but is wrapped in two sets of double-quotes when "call before play" option is used: your case. I want to use only a single set of double-quotes in both cases; i.e. "filepath"  instead of ""filepath"".

Since your script removes all the double-quotes, I think you don't care - am I correct?

I use the double quotes to protect against filepaths that contain spaces.

Ok, try LoadDVDV2.44 from my web site. I won't announce it yet until I get confirmation that it performs correctly with your script.

Update: Finally released as V2.46. Thanks to nightowl128 for testing and feedback.