This should work for you.
I wrote a custom adm to do this via group policy (for UK Keyboard Layout)
more than welcome to use and adapt it..
CLASS USER CATEGORY "Custom Settings" CATEGORY "Keyboard Layout" POLICY "Set UK Keyboard Layout" KEYNAME "Keyboard Layout\Preload" VALUENAME 1 VALUEON 00000809 VALUEOFF "" END POLICY ;Set UK Keyboard Layout END CATEGORY ;Keyboard Layout END CATEGORY ;Custom Settings
INSTRUCTIONS
Step 1: Save the above code as keyboard.adm file into the folder C:Windows\inf on the server
Step 2: Create and link a new GPO (call it something like “Keyboard Layout”)
Step 3: Edit the Keyboard Layout GPO
Step 4: In the Group Policy Editor Window; under User Configuration, right click Administrative Templates and choose Add Template
Step 5: select the keyboard.adm template and click OK until you are returned to the Group Policy Editor window
Step 6: with Templates still selected on the left hand side, select view from the toolbar, and filtering
Step 7: make sure the bottom 2 tick boxes (“only show configured policy settings” and “only show policy settings that can be fully managed”) are un-ticked
Step 8: Browse to the following setting (using the view on the left hand side) User Configuration > Administrative Templates > Custom Settings > Keyboard Layout
Step 9: Enable the policy setting listed on the right hand side (“Set UK Keyboard Layout”)