The name should contain Windows' LCID for that locale. You will get it added automatically to the file name by Keyboard Creator tool when you save a custom layout (LCID for the locale selected in property pane on the right).

InputLocale is something the keyboard sets automatically in response to system's language change. If you want to set the input language of a process that embeds the keyboard, set InputLanguageManager.Current.CurrentInputLanguage. If you use the keyboard in standalone mode and need to set language of external applications, you should be able to by sending WM_INPUTLANGCHANGEREQUEST Windows message to the application's main window like PostMessage(hWnd, WM_INPUTLANGCHANGEREQUEST, INPUTLANGCHANGE_FORWARD, MYLOCALE);

The image names stored with layouts can only be loaded from external files. Maybe you could use embedded images by mapping key codes to embedded image resources through key's data templates and some binding converters.

Regards,
Slavcho
Mindfusion