Just as an experiment, parsed out the keycodes listed on this page into an array, just use chArr[Key.getCode()]; to show which key was pressed.
Seems to work OK
chArr=["","","","","","","","","Backspace","Tab","","","","Enter","","","Shift","Control","","Pause/Break","Caps Lock","","","","","","","Esc","","","","","Spacebar","Page Up","Page Down","End","Home","Left Arrow","Up Arrow","Right Arrow","Down Arrow","","","","","Insert","Delete","","0","1","2","3","4","5","6","7","8","9","","","","","","","","A","B","C","D","E","F","G","H","I","J","K","L","M","N","O","P","Q","R","S","T","U","V","W","X","Y","Z","","","","","","Numpad 0","Numpad 1","Numpad 2","Numpad 3","Numpad 4","Numpad 5","Numpad 6","Numpad 7","Numpad 8","Numpad 9","Multiply","Add","","Subtract","Decimal","Divide","F1","F2","F3","F4","F5","F6","F7","F8","F9","","F11","F12","F13","F14","F15","","","","","","","","","","","","","","","","","","Num Lock","ScrLk","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","","",";","=",",","-",".","/","`","","","","","","","","","","","","","","","","","","","","","","","","","","","[","\\","]","#","`"];
kl=new Object();
kl.onKeyDown=function(){
_root[TextBoxName].text=chArr[Key.getCode()];
}
Key.addListener(kl);