Heres What My RunOnceEx.cmd looks like:

cmdow @ /HID
@echo off

SET KEY=HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\RunOnceEx

REG ADD %KEY% /V TITLE /D "Installing Applications" /f

REG ADD %KEY%\001 /VE /D "Preparing Installation..." /f
REG ADD %KEY%\001 /V 1 /D "%systemdrive%\install\prepare.cmd" /f

REG ADD %KEY%\010 /VE /D "DirectX 9.0b" /f
REG ADD %KEY%\010 /V 1 /D "%systemdrive%\install\DirectX 9.0b\DX9NTopk.exe /qn" /f

REG ADD %KEY%\015 /VE /D "MSN Messenger 6.2" /f
REG ADD %KEY%\015 /V 1 /D "%systemdrive%\install\MSN\MSN_Messenger_6.2.0133.msi /qn" /f

REG ADD %KEY%\020 /VE /D "Cmd Here Powertoy" /f
REG ADD %KEY%\020 /V 1 /D "%systemdrive%\install\PowerToys\CmdHerePowertoySetup.exe /qn" /f

REG ADD %KEY%\025 /VE /D "Image Resizer Powertoy" /f
REG ADD %KEY%\025 /V 1 /D "%systemdrive%\install\PowerToys\ImageResizerPowertoySetup.exe /qn" /f

REG ADD %KEY%\030 /VE /D "Slide Show Powertoy" /f
REG ADD %KEY%\030 /V 1 /D "%systemdrive%\install\PowerToys\SlideshowPowertoySetup.exe /qn" /f

REG ADD %KEY%\035 /VE /D "Tweak Ui Powertoy" /f
REG ADD %KEY%\035 /V 1 /D "%systemdrive%\install\PowerToys\TweakUiPowertoySetup.exe /qn" /f

REG ADD %KEY%\040 /VE /D "Importing Registry Tweaks" /f
REG ADD %KEY%\040 /V 1 /D "REGEDIT /S %systemdrive%\install\regtweaks.reg" /f

REG ADD %KEY%\045 /VE /D "Cleaning Up and Rebooting" /f
REG ADD %KEY%\045 /V 1 /D "%systemdrive%\install\cleanup.cmd" /f

EXIT

1: Windows cannot find 'C:\install\DirectX'. In your RunOnceEx, Your path to the directX file has spaces. That's causing windows to ignore everything after the first space. It's trying to execute the file 'C:\install\DirectX'. I'd recommend renaming your DirectX 9.0b folder to just DirectX and modify your RunOnceEx to reflect that.

As for your powertoys, the /qn switch will not work for these. That is for MSI installations.

If your tweakUI is the one downloaded from the microsoft website, it WON'T work.

Edit: You'll have to search the forum for using these powertoys.

Check out this page: http://unattended.msfn.org/xp/applications/powertoys.htm

You need to download the tweakui that was repackaged by Ytterbium.

Also, all other powertoys support the /s /v/qn switch.

Another thing you can do for your DirectX entry is change it to this:

REG ADD %KEY%\010 /V 1 /D "\"%systemdrive%\install\DirectX 9.0b\DX9NTopk.exe\" /qn" /f

That puts the entire pathname in quotes so that the spaces will parsed correctly.