I recently lamented about switching two keys on my new Lenovo Yoga. Big problem: In my office, I attach that notebook to a docking station and to that docking station I attach a keyboard. On that keyboard, all keys are precisely the way I want them to be. Therefore, I do not want to switch the Insert and End keys when I am docked. I ended up writing a little batch script based on this nice google code wiki entry for the registry update and this stackexchange answer to elevate the batch script:
if '%ERRORLEVEL%' == '0' goto run 
powershell "saps -filepath %0 -verb runas" >nul 2>&1
goto eof
REG QUERY "HKLM\SYSTEM\CurrentControlSet\Control\Keyboard Layout" ^
 /v "Scancode Map" >nul 2>&1 
IF '%ERRORLEVEL%' == '0' goto remove
<nul set /p ="> adding scancode map "
REG ADD "HKLM\SYSTEM\CurrentControlSet\Control\Keyboard Layout" ^
 /v "Scancode Map" /t REG_BINARY /f ^
 /d 00000000000000000300000052E04FE04FE052E000000000 >nul 2>&1 
IF '%ERRORLEVEL%' == '0' goto success
goto fail 
<nul set /p ="> removing scancode map "
REG DELETE "HKLM\SYSTEM\CurrentControlSet\Control\Keyboard Layout" ^
 /v "Scancode Map" /f >nul 2>&1 
IF '%ERRORLEVEL%' == '0' goto success
goto fail
echo failed.
goto eof
echo succeeded.
Sadly, it always requires a reboot for the changes to take effect.