Khmer Unicode Layout Widget for Apple Mac is a handy tool for someone who doesn’t remember all the Khmer alphabets positioned in the Khmer V2 keyboard layout. You bring up the Khmer Keyboard Layout anytime by pressing F12.
Extract the KhmerKeyboardLayout.wdgt.zip file, then double click on the widget (.wdgt) file to start the install process.
More info on how to install or disable a widget on Apple mac click here.
Press F12 to show the widget page.