I wrote a small program "ErrorLog" that can run inside the %Tools% directory and does that work:
Processing script: Set Keyboard
FileCopy - Failed to copy [V:\BCD\cds\XPP_DE_SP2\I386\KBDUS.DLL] to: [V:\OpenBuilder_047\Archive\Tweaks\Target\i386\system32\KBDUS.DLL]
RegHiveLoad - Failed to load registry hive: [Build] from file: [V:\OpenBuilder_047\Archive\Tweaks\Target\i386\system32\config\default]
RegWrite - Failed to write REG key in root key: [HKLM] Type: [0x1] Section: [Build\Keyboard Layout\Preload] Key: [1=00000409..]
RegWrite - Failed to write REG key in root key: [HKLM] Type: [0x1] Section: [Build\Control Panel\Keyboard] Key: [InitialKeyboardIndicators=2..]
RegHiveUnLoad - Failed to unload registry hive: [Build]
RegHiveLoad - Failed to load registry hive: [Build] from file: [V:\OpenBuilder_047\Archive\Tweaks\Target\i386\system32\setupreg.hiv]
RegWrite - Failed to write REG key in root key: [HKLM] Type: [0x1] Section: [Build\ControlSet001\Control\Keyboard Layout\DosKeybCodes] Key: [00000409=us..]
RegWrite - Failed to write REG key in root key: [HKLM] Type: [0x1] Section: [Build\ControlSet001\Control\Keyboard Layouts\00000409] Key: [Layout Text=409 English (United States)..]
RegWrite - Failed to write REG key in root key: [HKLM] Type: [0x1] Section: [Build\ControlSet001\Control\Keyboard Layouts\00000409] Key: [Layout Display Name=@%SystemRoot%\\system32\\input.dll,-5000..]
RegWrite - Failed to write REG key in root key: [HKLM] Type: [0x1] Section: [Build\ControlSet001\Control\Keyboard Layouts\00000409] Key: [Layout File=KBDUS.DLL..]
RegHiveUnLoad - Failed to unload registry hive: [Build]
Processing script: Screen resolution
RegHiveLoad - Failed to load registry hive: [Build] from file: [V:\OpenBuilder_047\Archive\Tweaks\Target\i386\system32\setupreg.hiv]
RegWrite - Failed to write REG key in root key: [HKLM] Type: [0x4] Section: [Build\ControlSet001\Services\VgaSave\Device0] Key: [DefaultSettings.BitsPerPel=32..]
RegWrite - Failed to write REG key in root key: [HKLM] Type: [0x4] Section: [Build\ControlSet001\Services\VgaSave\Device0] Key: [DefaultSettings.XResolution=800..]
RegWrite - Failed to write REG key in root key: [HKLM] Type: [0x4] Section: [Build\ControlSet001\Services\VgaSave\Device0] Key: [DefaultSettings.YResolution=600..]
RegHiveUnLoad - Failed to unload registry hive: [Build]
Processing script: Replace dll files
ExtractAllFiles - Failed to extract internal files from file: [V:\OpenBuilder_047\Projects\NanoXP\Tweak\Freedos32-Resources.script] Section:[Folder] Path to extract: [V:\OpenBuilder_047\Projects\NanoXP\Tweak\Target\I386\System32]
Processing script: Set CMD.EXE as default shell
RegHiveLoad - Failed to load registry hive: [Build] from file: [V:\OpenBuilder_047\Archive\Shell\Target\i386\system32\setupreg.hiv]
RegWrite - Failed to write REG key in root key: [HKLM] Type: [0x1] Section: [Build\Setup] Key: [CmdLine=cmd.exe..]
RegHiveUnLoad - Failed to unload registry hive: [Build]
Processing script: Create ISO
Failed to retrieve the dir size from: [V:\OpenBuilder_047\Archive\ISO\Target] - dir was not found
Failed to retrieve the file size from: [V:\OpenBuilder_047\ISO\nanoxp.iso] - file was not found
The program inclusive source code can be found here.
Have fun!
Peter