How to go about adding tab functionality?

tabtest.red

;do %/c/../tabtest.red										;-- Everything before the Red header is not a comment!!
Red [
	file: %tabtest.red
]

window-actors: object [ 			;-- actors for the window
	on-key: func [face [object!] event [event!]][
		case [
			event/key = #"^-" [
				print "TAB key caught by window face!" 
				'stop										;-- This 'stop stops the 
			]
			1 = 1 [
				prin "keystroke caught: " print event/key
]	]	]	]

; Main window creation, the visible part of the program ------------------
tab-win: layout [
	title "Tab focus test program"
	style label: text bold left 70

	origin 20x20
	
	label "Above"
	above-1: field 40 focus extra 'above-1					;-- just an idea to make a hook on this
	label "Also above"
	above-2: field 50 extra 'above-2

	return
	main-panel: tab-panel 600x500 [
		"Panel 1" [
			pan1-field1: field "" extra 'pan1-field1
			return
			pan1-field2: field "" extra 'pan1-field2
			return
			pan1-field3: field "" extra 'pan1-field3 [
				main-panel/selected: 2
				tab-win/selected: pan2-field1
			]
		]
		"Panel 2" [
			pan2-field1: field "" extra 'pan2-field1
			return
			pan2-field2: field "" extra 'pan2-field2
			return
			pan2-field3: field "" extra 'pan2-field3
		]
		"Panel 3" [
			pan3-field1: field "" extra 'pan3-field1
			return
			pan3-field2: field "" extra 'pan3-field2
			return
			pan3-field3: field "" extra 'pan3-field3
		]
	] 
	return
	btn-quit: button "Quit" [unview]
]

tab-win/actors: window-actors
view tab-win